Lincoln Corsair: Power Steering / Diagnosis and Testing - Power Steering

Normal Operation and Fault Conditions

There are 2 power sources for the PSCM , the high current power steering fuse, and the low current power steering fuse. Refer to the wiring diagrams to review the PSCM circuit for both the high current and low current fuse locations as well as the associated power and ground wiring. Open power steering fuse can occur when the power or ground wiring is shorted against another component or water intrusion in the respective connectors or connections.

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors

• NOTE: This procedure must be completed using FDRS. Do not clear DTCs until the FDRS procedure has completed.
    To complete the diagnosis, navigate to the FDRS Guided Routine tab and carry out the procedure Electronic Power Assist Steering (EPAS) Invalid or Missing Controller Area Network (CAN) Data.
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Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM is self monitoring and performs self tests at specific intervals (initial power up, power down, during normal operation, ect.) Each self test requires the voltage supply to the PSCM to be at or above a specific level (above 6 volts, above 9 volts, between 10 and 17 volts, ect.) for the test to take place. If one or more of the self tests should fail, the module sets one or more Diagnostic Trouble Codes (DTCs).

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U3000:xx Diagnostic Trouble Codes (DTCs) except for U3000:4B. This test does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify PSCM U3000:XX is present and provide diagnostics if DTC U3000:XX is currently present and active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• For DTC U3000:42, steering assist is not affected and there is no warning in the message center. The PSCM may transmit an invalid steering angle message over the HS-CAN .
• For DTC U3000:49, during the ignition cycle the DTC initially sets, the PSCM enters limp home mode and steering assist is gradually reduced until the PSCM enters manual mode. The PSCM sends a message to the IPC to display the STEERING ASSIST FAULT SERVICE REQUIRED in the message center.
• During the next ignition cycle after the DTC sets, If the PSCM is not already in manual mode the PSCM removes steering assist and enters manual mode. The module also transmits an invalid steering angle message over the HS-CAN and sends a message to the IPC to display the STEERING ASSIST FAULT SERVICE REQUIRED in the message center.
• The presence of DTC U3000:49 prevents the optional steering features; active park assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist system is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Heat shield missing
• Steering column internal failure
• Incorrect EPAS column installed
• Heavy loads on the EPAS column
• Excessive ambient temperatures

Visual Inspection and Pre-checks

• This DTC sets when the PSCM internal self tests detect a software or hardware internal error. This can be to internal faults in the PSCM or from water getting inside the PSCM . For additional fault setting information, refer to the PSCM DTC Chart.

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• HS-CAN concern
• PSCM

Visual Inspection and Pre-checks

• Workshop Manual diagnostics for another module not communicating with the PSCM must be carried out prior to entering this test.

• NOTE: This procedure must be completed using FDRS. Do not clear DTCs until the FDRS procedure has completed.
    To complete the diagnosis, navigate to the FDRS Guided Routine tab and carry out the procedure Electronic Power Assist Steering (EPAS) Invalid or Missing Controller Area Network (CAN) Data.
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NOTE: Customers may report an intermittent power steering concern that may not replicate during a test drive session. TSB , SSM or Diagnostic Trouble Codes (DTCs) may exist indicating the likely root cause. Retrieve all Diagnostic Trouble Codes (DTCs) for the vehicle, as well as TSB , SSM .

Normal Operation and Fault Conditions

there are 2 power sources for the PSCM , the high current power steering fuse, and the low current power steering fuse. Refer to the wiring diagrams to review the PSCM circuit for both the high current and low current fuse locations as well as the associated power and ground wiring. Open power steering fuse can occur when the power or ground wiring is shorted against another component or water intrusion in the respective connectors or connections.

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If lost communication or voltage Diagnostic Trouble Codes (DTCs) exist in the PSCM or other vehicle modules, possible source can be fuse(s) or wiring, terminals, or connectors
• If Diagnostic Trouble Codes (DTCs) other than lost communication or voltage exist in the PSCM or other vehicle modules, the possible source can be an internal fault in the PSCM or other vehicle modules.
• If no Diagnostic Trouble Codes (DTCs) are present in the PSCM or other vehicle modules, the concern could be addressed by a service article such as a TSB , GSB , SSM , or FSA .

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• PSCM internal fault
• Internal fault in other module(s) on the CAN

• Ignition ON.

• Using a diagnostic scan tool, retrieve the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules.

Normal Operation and Fault Conditions

Description

Description

• The steering wheel can vibrate or shake as well as resist turning into the next lane when the turn signals are not used to change lanes. This may be a normal operation of the Lane Keeping Assist feature.
• .

REFER to: Lane Keeping System - System Operation and Component Description (419-07 Lane Keeping System, Description and Operation).

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to the following diagnostic concerns:
• Steering wheel vibrates or resists turning

This test DOES NOT apply to any other DTC or symptom.

Diagnostic Strategy

Diagnostic Strategy

• Determine if the vehicle is equipped with the Lane Keeping Assist feature and educate the customer how the feature is activated, de-activated and properly used. Verify the vibration and turning resistance is no longer present when the Lane Keeping Assist feature is de-activated.

• Refer to the following sources of information on the PTS website:
• Owner's Literature - REFER to DRIVING AIDS
• Owner's Literature, Quick Reference Guide - REFER to FUNCTION
• Lane Keeping Reference Guide (all vehicles)

Possible Sources

• Normal operation of the Lake Keeping System

NOTE: Customers may report an intermittent power steering concern that may not replicate during a test drive session. TSB , SSM or Diagnostic Trouble Codes (DTCs) may exist indicating the likely root cause. Retrieve all Diagnostic Trouble Codes (DTCs) for the vehicle, as well as TSB , SSM .

Normal Operation and Fault Conditions

there are 2 power sources for the PSCM , the high current power steering fuse, and the low current power steering fuse. Refer to the wiring diagrams to review the PSCM circuit for both the high current and low current fuse locations as well as the associated power and ground wiring. Open power steering fuse can occur when the power or ground wiring is shorted against another component or water intrusion in the respective connectors or connections.

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors

• NOTE: This procedure must be completed using FDRS. Do not clear DTCs until the FDRS procedure has completed.
    To complete the diagnosis, navigate to the FDRS Guided Routine tab and carry out the procedure Electronic Power Assist Steering (EPAS) Invalid or Missing Controller Area Network (CAN) Data.
• 
  

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• HS-CAN concern
• PSCM

• NOTE: This procedure must be completed using FDRS. Do not clear DTCs until the FDRS procedure has completed.
    To complete the diagnosis, navigate to the FDRS Guided Routine tab and carry out the procedure Electronic Power Assist Steering (EPAS) Invalid or Missing Controller Area Network (CAN) Data.
• 
  

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

The EPAS system is designed to compensate for some steering issues (drift, pull, wander, etc.). However, if the steering issue is severe enough, the condition or symptom may become noticeable to the driver.

The system starts compensating when vehicle speed exceeds 40 km/h (25 mph) and the vehicle is traveling straight. The system compensates on any road crown condition; however, some amount of pull is present during, and shortly after, quick lane transitions. After driving straight on a constant road crown with both hands on the steering wheel for at least 45 seconds, the pull condition can be assessed. The system does not compensate when turning at low speeds. For the system to compensate, the driver's hands must remain on the steering wheel.

Drift describes what a vehicle with this condition does with the hands off the steering wheel. A vehicle-related drift, on a flat road, can cause a consistent deviation from the straight-ahead path and require constant steering input in the opposite direction to counteract the effect. Drift can be induced by conditions external to the vehicle, such as wind or road camber.

Pull is described as a tugging sensation on the steering wheel felt by the driver, which must be overcome to keep the vehicle going straight.

Wander is the tendency of the vehicle to require frequent, random left and right steering wheel corrections to maintain a straight path down a level road.

Possible Sources

• Alignment
• Tires
• Steering gear mounts
• Steering column shaft U-joints
• Steering column
• Suspension components
• Steering gear

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

With a fully charged battery and the ignition ON, the EPAS system provides adequate assist to maneuver the vehicle and return to the straight-ahead position with little difficulty. The assist provided by the EPAS system should be smooth and consistent at all times. The steering and suspension components should be free of any binding conditions and should not interfere with the steering assist provided by the EPAS system.

If the steering wheel is held at the end of travel for more than 2 seconds, the level of assistance is noticeably reduced by the EPAS system. This is a normal condition programmed into the PSCM to protect the system from permanent damage.

Poor returnability or sticky steering is used to describe the poor return of the steering wheel to center after a turn or steering correction is completed.

Possible Sources

• Fuses
• Wiring, terminals or connectors
• Under inflated or mismatched tires
• Alignment
• Binding suspension components
• Binding steering gear
• Binding steering gear bearings
• Binding steering column shaft dash panel seal
• Binding lower steering column shaft coupling or U-joint
• Outer tie-rod ends
• Inner tie rods
• Loose, worn or damaged steering linkage
• Steering gear internal failure
• EPAS column internal failure

Visual Inspection and Pre-checks

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure PSCM fuses in the BJB are OK.
• Make sure there are no obvious loose, worn, damaged or binding suspension components.

NOTE:

• This message appears when a condition has been detected in the EPAS system requiring the PSCM to disable the system (remove assist) to help prevent the system from sustaining any possible damage. This message (and related symptom) may be cleared when the ignition key is cycled and may not be present at the time of diagnosis.

• This message appears if a condition exists has been detected in the EPAS system requiring the PSCM to immediately reduce steering assist, gradually reduce assist or disable assist completely to help prevent the system from sustaining any possible damage. This message (and related symptom) may be cleared when the ignition key is cycled and may not be present at the time of diagnosis.

Possible Sources

NOTE:

• Wheel hub bearings can produce noise after achieving 56 km/h (35 mph) while driving straight if they are worn.

• Front end noises while driving straight involve parts which rotate continuously while the road wheels are rotating. Typically not a steering gear.

• Noises can also be caused by loose or un-retained parts affected by wind.

Possible Sources

• Possible rotating sources:
• Axle shafts or halfshafts
• Carrier bearing (noise is typically felt through the console)
• Drive shafts
• Transfer case assembly (if equipped)
• Wheel hub and wheel bearings (typically higher speeds)
• Possible Wind Sources:
• Air dams
• Heat shields
• Radiator ducts or shields
• Wheel well splash shields

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Excessive steering wheel free play is a condition in which there is too much steering wheel movement before the wheels move. The EPAS system is designed to compensate for some steering wheel free play, however a small amount of steering wheel free play is considered normal.

Possible Sources

• Steering column shaft U-joints
• Loose, damaged or worn inner or outer tie rods
• Steering gear internal failure
• EPAS column internal failure

NOTE:

• This message appears when a condition has been detected requiring the PSCM to disable the system (remove assist) to help prevent the system from sustaining any possible damage. This message (and related symptom) may be cleared when the ignition is cycled and may not be present at the time of diagnosis or may not clear until the condition is repaired.

• This message appears if a condition exists (high friction for example) putting extra load on the EPAS system. Steering assist remains for the current ignition cycle. If the ignition is turned OFF and then back ON, STEERING FAULT SERVICE NOW appears in the message center and steering assist is removed until the condition is repaired.

Possible Sources

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Steering Gears That Appear To Be Leaking Power Steering Fluid

Steering Gears That Appear To Be Leaking Power Steering Fluid

• EPAS gears are not filled with power steering fluid.
• Only HPAS gears are filled with power steering fluid.
• Only HPAS gears can leak power steering fluid.

Pinpoint Test Purpose

Pinpoint Test Purpose

• To provide diagnostic direction about external fluids leaking onto EPAS gears and components.

External Sources Of Fluids

External Sources Of Fluids

• Engine coolant
• Engine oil
• Transmission fluid
• Brake fluid
• Fluid from nearby reservoir bottles

Possible Sources

• External fluid source dripping or leaking onto the steering gear

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM uses a thermistor to monitor the internal temperature of the EPAS gear. This DTC appearing by itself does not indicate a fault condition in the steering system. Diagnose all other EPAS Diagnostic Trouble Codes (DTCs) before diagnosing B1D23:4B.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC B1D23:4B only. It does not apply to any other module except PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults.

Pinpoint Test Purpose

Pinpoint Test Purpose

• This test inspects the steering gear and the surrounding engine compartment for hot components, missing heat shields or a damaged steering gear housing creating an opening into the steering gear.

Diagnostic Aids

Diagnostic Aids

• The PSCM reporting only DTC B1D23:4B does not indicate a fault in the PSCM . It indicates an over-temperature condition due to ambient conditions or a heavy load on the EPAS system. An example of a heavy load would be multiple parking lot maneuvers over a short duration of time with low tire pressure or towing for long distances followed by multiple parking maneuvers.
• The thermistor used by the PSCM is calibrated for 80ºC (176ºF) and as ambient temperature decreases, so does the accuracy of the sensor. At room temperature and lower, the sensor is +/- 20ºC (68ºF).
• The presence of DTC B1D23:4B prevents the optional steering features; active park assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Heavy loads on the steering gear
• Excessive ambient temperatures
• PSCM

Visual Inspection and Pre-checks

• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the voltage supplied by the 12 volt battery and charging system and sets the appropriate DTC when necessary.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U3003:16, U3003:17, or U3003:68 only. It does not apply to any other module except PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults.

Pinpoint Test Purpose

Pinpoint Test Purpose

• This test verifies the PSCM fuses in the BJB and the high current BJB are OK, the PSCM wiring harness power and ground connections are OK. The test also verifies the charging system and battery state of charge.

Diagnostic Aids

Diagnostic Aids

• For some instances the message center may display: STEERING ASSIST FAULT SERVICE REQUIRED. This does not indicate a concern with the PSCM if only DTC U3003:XX is present. The 12 volt battery health should be evaluated.
• The PSCM reporting only DTC U3003:16, U3003:17 or U3003:68 does not indicate a concern with the PSCM . DO NOT install a new EPAS assembly or PSCM if one or more of these Diagnostic Trouble Codes (DTCs) is set.
• The presence of DTC U3003:16, U3003:17, U3003:18 or U3003:68 prevents the optional steering features; Active Park Assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) feature from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated. The presence of one of these Diagnostic Trouble Code's may also result in heavier than usual steering efforts.
• When DTC U3003:16 is set, the PSCM reduces power steering assist to a predetermined current draw. If EPAS operation exceeds this current limit, the PSCM continues to reduce steering assist until the current draw is below the limit or until assist is removed completely.

DTC Fault Trigger Conditions

Possible Sources

• Fuses
• Wiring, terminals or connectors
• Charging system concern
• 12 volt Battery
• PSCM

Visual Inspection and Pre-checks

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure the vehicle battery terminals are tightened to their correct torque specifications.
• Make sure all PSCM fuses in the BJB and high current BJB are OK.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• When the ignition is set to OFF, the PSCM remains powered up for a short period of time to store data in memory. When the ignition is set to ON, the PSCM retrieves this information and if the information is missing or corrupted a DTC is set.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U3001:68 only. This test does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify PSCM U3001:68 is present and provide diagnostics if DTC U3001:68 is currently present and active in the PSCM .

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals, or connectors
• 12-volt battery
• Charging system

Visual Inspection and Pre-checks

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure the vehicle battery terminals are tightened to their correct torque specifications.
• Make sure all PSCM fuses in the BJB and high-current BJB are OK.

Normal Operation and Fault Conditions

Description

Description

• When the battery voltage to the PSCM is greater than 10 volts with the ignition ON and there are no Diagnostic Trouble Codes (DTCs) present, the PSCM runs a self test of the system software. If an error is detected, a DTC is set and the EPAS enters into a limited operation mode.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U3000:4B Control Module: Over Temperature only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verifyPSCM DTC U2016:xx is present and provide diagnostics if DTC U2016:xx is currently active in the PSCM .

DTC Fault Trigger Conditions

Possible Sources

• EPAS column assembly internal failure
• Heavy loads on the EPAS system
• Excessive ambient temperatures

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• While the ignition is ON and the voltage supply to the PSCM is above 6 volts, the module monitors the motor inside the EPAS column to calculate the relative and actual steering wheel angle. This value is transmitted to other modules over the HS-CAN .

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC C1B00:49 or C1B00:62 only. It DOES NOT apply to any other modules or Diagnostic Trouble Codes (DTCs).

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• Verify PSCM DTC C1B00:XX is present. Verify PSCM wiring harness and electrical connectors are in good condition.

Diagnostic Aids

Diagnostic Aids

• When DTC C1B00:49 is set, the PSCM removes steering assist, enters into manual mode and transmits an invalid steering angle message over the HS-CAN . The module also sends a message to the IPC to display POWER STEERING ASSIST FAULT in the message center.

DTC Fault Trigger Conditions

Possible Sources

• Steering column internal failure
• PSCM internal failure

Visual Inspection and Pre-checks

• This DTC sets if the sum of the 2 steering shaft torque sensors do not equal a specified voltage level. This can occur if the wiring harness is damaged, chewed or the connectors are loose or damaged. An internal steering column or PSCM fault can also cause this DTC set. For additional fault setting information, refer to the PSCM DTC Chart.
• Refer to Steering GSB for additional connector and wiring inspection tips

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM continually monitors the steering shaft torque sensor when the ignition is ON and the voltage supply to the sensor is between 5.26 and 4.71 volts.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC C200B Steering Shaft Torque Sensor 1 only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify PSCM C200B:XX is present and provide diagnostics if DTC C200B:XX is currently present and active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• During the ignition cycle the DTC initially sets, the PSCM either enters reduced assist mode or steering assist is gradually reduced until the PSCM enters manual mode.
• During the next ignition cycle after the DTC sets, if the PSCM is not already in manual mode the PSCM removes steering assist and enters manual mode. The module also transmits an invalid steering angle message over the HS-CAN and sends a message to the IPC to display the STEERING ASSIST FAULT SERVICE REQUIRED in the message center.

DTC Fault Trigger Conditions

Possible Sources

• Torque sensor electrical connector loose or damaged
• Torque sensor wiring damaged
• Steering column internal failure

Visual Inspection and Pre-checks

• This DTC sets when the steering torque sensor input to the PSCM is out of range or does not agree with other PSCM inputs. This is most likely due to internal faults in the PSCM . For additional fault setting information, refer to the PSCM DTC Chart.
• Refer to Steering GSB for additional connector and wiring inspection tips

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM continually monitors the motor position angle sensor when the ignition is ON and the voltage supply to the PSCM is above 10 volts.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC C200D Motor Rotation Angle Sensor only. It does not apply to any other module except the PSCM.

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify PSCM C200D:xx is present and provide diagnostics if DTC C200D:xx is currently present and active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• During the ignition cycle the DTC initially sets, the PSCM either enters manual mode, reduced assist mode or steering assist is gradually reduced until the PSCM enters manual mode.
• During the next ignition cycle after the DTC sets, if the PSCM is not already in manual mode the PSCM removes steering assist and enters manual mode. The module also transmits an invalid steering angle message over the CAN and sends a message to the IPC to display the STEERING ASSIST FAULT SERVICE REQUIRED in the message center.

DTC Fault Trigger Conditions

Possible Sources

• EPAS column internal failure

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• There are multiple conditions (overheating protection, high voltage, low voltage, etc.) which result in limited or reduced assist from the EPAS system. Address all existing PSCM Diagnostic Trouble Codes (DTCs) prior to diagnosing any assist symptoms.
• With a fully charged battery and the ignition ON, the EPAS system provides adequate assist to maneuver the vehicle and return to the straight-ahead position with little difficulty. The assist provided by the EPAS system should be smooth and consistent at all times. The steering and suspension components should be free of any binding conditions and should not interfere with the steering assist provided by the EPAS system.
• If the steering wheel is held at the end of travel for more than 2 seconds, the level of assistance is noticeably reduced by the EPAS system. This is a normal condition programmed into the PSCM to protect the system from permanent damage.
• Lack of assist or inconsistent assist is experienced when the steering wheel effort is higher than normal. Hard steering can remain constant through the full turn or occur near the end of a turn. It is important to know the difference between hard steering or lack of assist and poor returnability or sticky steering.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to the symptom "Lack of Assist, Intermittent or Inconsistent Assist". It DOES NOT apply to any other DTC or symptom.
• This pinpoint test DOES NOT apply to:
  • Pull or drift concerns
  • Lane keeping concerns
  • Uneven steering effort concerns

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM , wiring harness and connections are working correctly. This test also verifies the existence of a low battery state of charge.

Possible Sources

• Fuse
• Wiring, terminals or connectors
• 12-volt battery
• Suspension components
• Steering gear internal failure
• Loose, damaged or worn inner or outer tie rods
• EPAS column internal failure

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM receives messages from other modules through 2 connectors: the PSCM -A (or B) 3-pin connector at the gear and the multi-pin in-line connector in the engine compartment. The in-line connector receives messages from the other modules into the PSCM wiring harness. The PSCM wiring harness uses the VDB wiring to carry the messages from the in-line connector to the PSCM -A (or B) 3-pin connector. If any of the connector pins or VDB communication wires are loose or damaged, the PSCM cannot properly receive messages from other modules.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to DTC U0420:xx Invalid Data Received from the Power Steering Control Module, and is set by other modules. It DOES NOT apply to any other DTC .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the condition of the battery state of charge, the PSCM wiring harness and electrical connectors. The test checks battery state of charge and checks the connectors and wiring from the PSCM 3-pin connector at the PSCM to the in-line connector in the passenger compartment.

Possible Sources

• Fuse
• Wiring, terminals or connectors
• Network communication concern
• 12-volt battery
• Charging system concern
• Module internal failure

NOTE: When DTC U2016:48 is set, the PSCM remains in normal operation mode, but features such as Active Nibble Control, Pull-Drift Compensation, Lane Departure Warning, Lane Keep Assist, ect. are disabled.

Normal Operation and Fault Conditions

Description

Description

• When the battery voltage to the PSCM is greater than 10 volts with the ignition ON and there are no Diagnostic Trouble Codes (DTCs) present, the PSCM runs a self test of the system software. If an error is detected, a DTC is set and the EPAS enters into a limited operation mode.
• REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).
  

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U2016 Control Module Main Software only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verifyPSCM DTC U2016 is present and provide diagnostics if DTC U2016 is currently active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• During the ignition cycle the DTC U2016:47 initially sets, the PSCM either enters limp home mode and steering assist is gradually reduced until the PSCM enters manual mode. The PSCM sends a message to the IPC to display STEERING ASSIST FAULT SERVICE REQUIRED in the message center.

• During the next ignition cycle after DTC U2016:47 sets, if the concern is still present, the PSCM removes steering assist and enters manual mode. The module also transmits an invalid steering angle message over the HS-CAN and sends a message to the IPC to display the STEERING ASSIST FAULT SERVICE REQUIRED in the message center.
• When DTC U2016:48 is set, the PSCM remains in normal operation mode, but all steering features; Active Nibble Control, Pull-Drift Compensation, Evasive Steering Assist (ESA), Lane Departure Warning (LDW), Lane Keep Assist (LKA) and Lane Centering Assist (LCA) may be disabled.

DTC Fault Trigger Conditions

Possible Sources

• PSCM internal failure

Visual Inspection and Pre-checks

• This DTC sets when the PSCM internal self tests detect a software internal error. Consult the DTC Index for additional information if needed.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• When a new EPAS gear is installed, the PSCM must be configured with the vehicle information. Configuration is checked during initial PSCM power up (ignition ON) with the voltage supply to the PSCM greater than 10 volts.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U2100:00 only. This test does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify PSCM U2100 is present and provide diagnostics if DTC U2100 is currently present and active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• If DTC U2100:00 is present the steering assist is set to a reduced steering assist mode.

DTC Fault Trigger Conditions

Possible Sources

• PSCM not configured
• PSCM configuration not complete

NOTE: This message appears when a condition has been detected in the EPAS system requiring the PSCM to disable the system (remove assist) to help prevent the system from sustaining any possible damage. This message (and related symptom) cannot be cleared until the condition is repaired.

Possible Sources

Normal Operation and Fault Conditions

Description

Description

• Due to various steering column hardware versions, a new PSCM must be calibrated or flashed with the correct level of operating software and matching calibration files.

Diagnostic Aid

Diagnostic Aid

• For additional information on PMI , REFER to: Module Programming (418-01 Module Configuration, General Procedures).
  .

DTC Fault Trigger Conditions

Possible Sources

• PSCM not configured.
• PSCM configuration not complete.

Visual Inspection and Pre-checks

• Refer to Steering GSB for additional connector and wiring inspection tips

Normal Operation and Fault Conditions

Description

Description

• When a new EPAS column is installed, the PSCM is blank and must be configured with the vehicle information. Configuration is checked during initial PSCM power up (ignition ON) with the voltage supply to the PSCM greater than 6 volts.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U2300 Central Configuration not complete only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verifyPSCM DTC U2300 is present and provide diagnostics if DTC U2300 is currently active in the PSCM .

Diagnostic Aids

Diagnostic Aids

• REFER to: Module Configuration - System Operation and Component Description (418-01 Module Configuration, Description and Operation).
  

DTC Fault Trigger Conditions

Possible Sources

• PSCM not configured
• PSCM configuration not complete

Visual Inspection and Pre-checks

• This DTC is set if the complete PSCM configuration was not carried out or if the configuration fails.

NOTE: Noises over bumps and rough roads involve parts which move and contact during an up and down motion.

Possible Sources

• Heat shields
• Stabilizer bar insulators or links
• Front shock brackets or strut mounts
• Loose steering gear tie rods
• Loose steering gear bolts
• Loose front brake calipers or pins
• Loose lower control arm-to-subframe bolts or bushings
• Loose ball joint
• Loose exhaust heat shield, isolators or brackets
• Subframe to body attachments points
• Upper or lower steering shaft
• Internal or external steering gear stops

• Ignition OFF.

• Check OASIS for any applicable noise TSB , GSB , SSM , or FSA relating to the following components:
  • Dash boots
  • Front axles
  • Motor mounts
  • Shocks
  • Struts
  • Suspension control arms and links
  • Sway bars
  • Wheel hubs

• Drive the vehicle and attempt to verify the noise.

• Using a good light source, visually inspect the following components for a potential concern (loose, damaged, worn, broken, rubbing):
  • Springs, shocks, struts, strut bearings, bushings or jounce bumpers
  • Stabilizer bar links and isolators
  • Tires
  • Tie-rod ends
  • Upper and lower steering column shaft
  • Steering stops
  • Loose steering gear mounts or bolts
  • Front brake caliper, caliper pins or brake discs
  • Front control arm and bushings
  • Front halfshafts and bearings (if equipped)
  • Subframe or crossmember condition, mounts or fasteners
  • Engine or transmission mounts
  • Loose lower control arm-to-subframe bolts
  • Loose ball joint
  • Loose exhaust head shield, isolators or brackets

• Using a listening device, such as Chassis Ears:
  • Install the listening device on the left and front strut towers.
  • Prepare the vehicle for a road test.
  • Using an assistant, attempt to duplicate the noise while listening to the device.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the left strut tower.
    • If loudest, inspect the strut tower area and attachments for looseness and wear.
  • Attach probe 2 to the left coil spring.
    • If loudest, inspect the upper strut bearing assembly for looseness and wear.
  • Attach probe 3 to the left lower control arm-to-subframe attachment point.
    • If loudest, inspect the control arm and bushings, subframe and bushings, sway bar bushings and links (common), and associated bolts for looseness and wear.
  • Attach probe 4 to the steering gear housing.
    • If loudest, inspect the inner and outer tie rods, mounting bushings, bolts and input shaft for looseness and wear. Place hands on steering shaft boot to verify if noise or vibration is transferring into steering gear (common). Verify whether other nearby components are transferring noise vibration into steering gear (common).

• Using an assistant, test drive the vehicle and listen to the 4 probes.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the right strut tower.
    • If loudest, inspect the strut tower area and attachments for looseness and wear.
  • Attach probe 2 to the right coil spring.
    • If loudest, inspect the upper strut bearing assembly for looseness and wear.
  • Attach probe 3 to the right lower control arm-to-subframe attachment point.
    • If loudest, inspect the control arm and bushings, subframe and bushings, sway bar bushings and links (common), and associated bolts for looseness and wear.
  • Attach probe 4 to the steering gear housing.
    • If loudest, inspect the inner and outer tie rods, mounting bushings, bolts and input shaft for looseness and wear. Place hands on steering shaft boot to verify if noise or vibration is transferring into steering gear (common). Verify whether other nearby components are transferring noise vibration into steering gear (common).

• Using an assistant, test drive the vehicle and listen to the 4 probes.

NOTE: NOTE: The steering gear is central to steering system and noises may be transferred to it from other nearby components.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the center of the subframe (or engine crossmember for body-on-frame vehicles).
    • If loudest, inspect the subframe, subframe mounts and any attaching hardware (sway-bar bushing mounts) for correct torque specifications, damage, wear, or witness marks. Inspect the engine and transmission mounts for debris, correct torque specification, damage, or wear.
  • Attach probe 2 to the bulkhead.
    • If loudest, inspect the bulkhead for damage or loose components (brackets, tubes, wiring harnesses, bushings).
  • Attach probe 3 to the center of the steering gear housing.
    • If loudest, insect the steering gear inner and outer tie-rods, mounting bushings, wiring harnesses and related components. Inspect the input shaft, boot and slip-joint lubrication. Place hands on the steering shaft boot and check for a vibration or noise transferring into the steering gear.

• Using an assistant, test drive the vehicle and listen to the 3 probes.

• Using a strong light source, visually inspect the following items:
  • steering gear-to-sub frame attachment points
  • input shaft-to-steering gear attachment point
  • outer tie-rod attachment points

• Verify the following fasteners are tightened to specifications (Refer to Section 211-02 in the Workshop Manual for correct torque specifications):
  • Steering gear-to-sub frame bolts
  • Input shaft-to-steering gear bolt
  • Outer tie-rod nuts

NOTE: Interior cabin noises involve parts moving or contacting during a steering wheel turn or interior parts moving or contacting during steering column tilt or telescopic operations.

Possible Sources

• Steering column shrouds
• Steering shafts and steering shaft joints
• Steering shaft boots or seals
• Clockspring (when lubricant on the clockspring is dry or drying)
• Steering column tilt or telescoping motor (if equipped)
• Shifter cables (if equipped)
• EPAS column motor
• Adaptive front steering motor (if equipped)

NOTE: Exterior front end noises when turning at slow speeds involve parts which move, rotate or make contact during a partial or full turn. Please note whether the vehicle has column mounted EPAS, steering gear mounted EPAS or adaptive steering.

Possible Sources

• Springs, shocks, struts and bearings or bushings (most common)
• Tires
• Steering gear internal stops (full turn)
• External steering stops (full turn)
• Steering tie rods (loose)
• Loose steering gear mounts or bolts
• Stabilizer bar insulators or links
• Integrated front wheel ends (4x4 only)
• Front control arms and bushings
• Front halfshaft and bearings (ting or ping metallic noise at slow speeds) (if equipped)
• Subframe or crossmember condition, mounts or fasteners
• Engine or transmission mounts

• Ignition OFF.

• Check OASIS for any applicable noise TSB , GSB , SSM , or FSA relating to the following components:
  • Dash boots
  • Front axles
  • Motor mounts
  • Shocks
  • Struts
  • Suspension control arms and links
  • Sway bars
  • Wheel hubs

• Drive the vehicle and attempt to verify the noise.

• Using a good light source, visually inspect the following components for a potential concern (loose, damaged, worn, broken, rubbing):
  • Springs, shocks, struts, strut bearings, bushings or jounce bumpers
  • Stabilizer bar links and isolators
  • Tires
  • Tie-rod ends
  • Upper and lower steering column shaft
  • Steering stops
  • Loose steering gear mounts or bolts
  • Front brake caliper, caliper pins or brake discs
  • Front control arm and bushings
  • Front halfshafts and bearings (if equipped)
  • Subframe or crossmember condition, mounts or fasteners
  • Engine or transmission mounts
  • Loose lower control arm-to-subframe bolts
  • Loose ball joint
  • Loose exhaust head shield, isolators or brackets

• Using a listening device, such as Chassis Ears:
  • Install the listening device on the left and front strut towers.
  • Prepare the vehicle for a road test.
  • Using an assistant, attempt to duplicate the noise while listening to the device.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the left strut tower.
    • If loudest, inspect the strut tower area and attachments for looseness and wear.
  • Attach probe 2 to the left coil spring.
    • If loudest, inspect the upper strut bearing assembly for looseness and wear.
  • Attach probe 3 to the left lower control arm-to-subframe attachment point.
    • If loudest, inspect the control arm and bushings, subframe and bushings, sway bar bushings and links (common), and associated bolts for looseness and wear.
  • Attach probe 4 to the steering gear housing.
    • If loudest, inspect the inner and outer tie rods, mounting bushings, bolts and input shaft for looseness and wear. Place hands on steering shaft boot to verify if noise or vibration is transferring into steering gear (common). Verify whether other nearby components are transferring noise vibration into steering gear (common).

• Using an assistant, test drive the vehicle and listen to the 4 probes.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the right strut tower.
    • If loudest, inspect the strut tower area and attachments for looseness and wear.
  • Attach probe 2 to the right coil spring.
    • If loudest, inspect the upper strut bearing assembly for looseness and wear.
  • Attach probe 3 to the right lower control arm-to-subframe attachment point.
    • If loudest, inspect the control arm and bushings, subframe and bushings, sway bar bushings and links (common), and associated bolts for looseness and wear.
  • Attach probe 4 to the steering gear housing.
    • If loudest, inspect the inner and outer tie rods, mounting bushings, bolts and input shaft for looseness and wear. Place hands on steering shaft boot to verify if noise or vibration is transferring into steering gear (common). Verify whether other nearby components are transferring noise vibration into steering gear (common).

• Using an assistant, test drive the vehicle and listen to the 4 probes.

NOTE: NOTE: The steering gear is central to steering system and noises may be transferred to it from other nearby components.

• Using a listening device, such as Chassis Ears:
  • Attach probe 1 to the center of the subframe (or engine crossmember for body-on-frame vehicles).
    • If loudest, inspect the subframe, subframe mounts and any attaching hardware (sway-bar bushing mounts) for correct torque specifications, damage, wear, or witness marks. Inspect the engine and transmission mounts for debris, correct torque specification, damage, or wear.
  • Attach probe 2 to the bulkhead.
    • If loudest, inspect the bulkhead for damage or loose components (brackets, tubes, wiring harnesses, bushings).
  • Attach probe 3 to the center of the steering gear housing.
    • If loudest, insect the steering gear inner and outer tie-rods, mounting bushings, wiring harnesses and related components. Inspect the input shaft, boot and slip-joint lubrication. Place hands on the steering shaft boot and check for a vibration or noise transferring into the steering gear.

• Using an assistant, test drive the vehicle and listen to the 3 probes.

• Using a strong light source, visually inspect the following items:
  • steering gear-to-sub frame attachment points
  • input shaft-to-steering gear attachment point
  • outer tie-rod attachment points

• Verify the following fasteners are tightened to specifications (Refer to Section 211-02 in the Workshop Manual for correct torque specifications):
  • Steering gear-to-sub frame bolts
  • Input shaft-to-steering gear bolt
  • Outer tie-rod nuts

NOTE: Noises when accelerating or decelerating involve parts which move during an acceleration tip-in (pressing foot on gas pedal) or parts which move during deceleration tip-out (when taking foot off gas pedal). These noises are not typically associated with the steering gear.

Possible Sources

• Steering shaft slip joints or lower input shaft (requires lubrication)
• Roll restrictor
• Powertrain mounts
• Exhaust heat shield (tinny rattle)
• Exhaust isolators and brackets
• Subframe mounts
• Engine to chassis wiring, tubes, brackets (loose or out of position)
• Halfshafts (if equipped)
• Mid-shaft bearing (right hand halfshaft)

• Test drive the vehicle, determine if the noise occurs only during braking or if the noise occurs during braking, acceleration and deceleration.

• NOTE: Noise sources can be identified by stethoscope or hands-on during vehicle rocking. Tip-in and tip-out noise not usually steering gear related. Prepare the vehicle for testing in a quiet area on level ground.
  • Steer the front wheels into the straight-ahead position.
  • Shift the transmission into PARK (automatic transmission) or THIRD (manual transmission).
  • Shut the engine off.
  • Release the parking brake.
  • Open the hood.

• Rock the vehicle backwards and forwards by pushing on the front bumper and attempt to locate the source of the noise.
  • Rocking the vehicle causes the engine mounts to flex, resulting in the movement of several components.

• Possible noise sources could be, but are not limited to:
  • Steering column shaft slip joint
  • Transmission or engine mounts
  • Roll restrictor
  • Subframe mounts
  • Axle shafts or halfshafts
  • Drive shafts
  • All coolant tubes, air conditioning tubes and wiring harnesses
  • Exhaust hangars and other related exhaust components

• With the transmission in NEUTRAL, position the vehicle on a hoist.
  REFER to: Jacking and Lifting - Overview (100-02 Jacking and Lifting, Description and Operation).
  

• Using a strong light source, visually inspect the following components for a potential concern (loose, damaged, broken):
  • Engine mounts
  • Transmission mounts
  • Roll restrictors
  • Heat shield(s) (tinny rattle)
  • Steering gear shield(s)
  • Exhaust isolators and bracket
  • Steering column shaft slip joints (dry condition)
  • Subframe mounts
  • Engine or chassis wiring, tubes or brackets (loose or out of position)
  • Halfshafts or driveshafts
  • Mid-shaft bearing (if equipped)

Normal Operation and Fault Conditions

The PSCM calculates steering wheel rotation speed, angle and direction of rotation and sends the information to the ABS module over the CAN . If the information is incorrect, invalid or corrupted, the ABS module sets one or more Diagnostic Trouble Codes (DTCs).

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to mechanical concerns with the PSCM resulting in ABS module DTC C006B:xx, ABS module DTC C0051:xx or false activation only.

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• This pinpoint test checks both the driving events and mechanical component conditions which can affect the steering wheel angle comparison between the ABS module and the PSCM .

Diagnostic Aids

Diagnostic Aids

• ABS module Diagnostic Trouble Codes (DTCs) C006B:xx and C0051:xx set when the comparison between the ABS module steering angle information and the PSCM steering angle information is outside of the expected range. Both mechanical and electrical components may cause this concern.

DTC Fault Trigger Conditions

Possible Sources

• Tire pressure
• Wheel speed sensor
• Incorrectly mounted RCM
• Network communication concern
• Incomplete or incorrect stability control sensor calibration
• Wheels and tires
• Front suspension components
• Steering system components
• RCM
• PSCM

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• ABS module Diagnostic Trouble Codes (DTCs) C006B:xx and C0051:xx set when the comparison between the ABS module steering angle information and the PSCM steering angle information is outside of the expected range. Both mechanical and electrical components may cause this concern.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to electrical concerns with the PSCM resulting in ABS module DTC C006B:xx, ABS module DTC C0051:xx or ABS false activation only.

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• This pinpoint test checks both the PSCM and the associated electrical wiring which can affect the steering wheel angle comparison between the ABS module and the PSCM .

Possible Sources

• PSCM Internal Failure Diagnostic Trouble Codes (DTCs)
• PSCM Network Lost Communication Diagnostic Trouble Codes (DTCs)
• PSCM Network Invalid Data Diagnostic Trouble Codes (DTCs)
• Starter, alternator, charging system voltage levels low
• Steering wiring harness, grounds or connectors
• Non-steering wiring harness, grounds or connectors

NOTE:

• If the noise occurs while braking AND during tip-in or tip-out, this is not typically a steering gear related noise.

• Noises when braking involve parts which move during braking.

Possible Sources

• Caliper anchors, calipers or brake pads
• Top strut mount or bearings (if equipped)
• Lower control arm attachment to sub frame bushings and bolts
• Engine to chassis wiring, tubes or brackets (loose or out of position)
• Exhaust isolators and brackets
• Subframe mounts
• Powertrain mounts or engine roll restrictor mounts
• Exhaust isolators or brackets
• Steering shaft slip joints

• Test drive the vehicle, determine if the noise occurs only during braking or if the noise occurs during braking, acceleration and deceleration.

• NOTE: Noise sources can be identified by stethoscope or hands-on during vehicle rocking. Tip-in and tip-out noise not usually steering gear related. Prepare the vehicle for testing in a quiet area on level ground.
  • Steer the front wheels into the straight-ahead position.
  • Shift the transmission into PARK (automatic transmission) or THIRD (manual transmission).
  • Shut the engine off.
  • Release the parking brake.
  • Open the hood.

• Rock the vehicle backwards and forwards by pushing on the front bumper and attempt to locate the source of the noise.
  • Rocking the vehicle causes the engine mounts to flex, resulting in the movement of several components.

• Possible noise sources could be, but are not limited to:
  • Steering column shaft slip joint
  • Transmission or engine mounts
  • Roll restrictor
  • Subframe mounts
  • Axle shafts or halfshafts
  • Drive shafts
  • All coolant tubes, air conditioning tubes and wiring harnesses
  • Exhaust hangars and other related exhaust components

• With the transmission in NEUTRAL, position the vehicle on a hoist.
  REFER to: Jacking and Lifting - Overview (100-02 Jacking and Lifting, Description and Operation).
  

• Using a strong light source, visually inspect the following components for a potential concern (loose, damaged, broken):
  • Engine mounts
  • Transmission mounts
  • Roll restrictors
  • Heat shield(s) (tinny rattle)
  • Steering gear shield(s)
  • Exhaust isolators and bracket
  • Steering column shaft slip joints (dry condition)
  • Subframe mounts
  • Engine or chassis wiring, tubes or brackets (loose or out of position)
  • Halfshafts or driveshafts
  • Mid-shaft bearing (if equipped)

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0100 Lost Communication with the PCM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the PCM and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the PCM , refer to the Network Message List in Section 211-02 of the Workshop Manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U0100:00.

DTC Fault Trigger Conditions

Possible Sources

• Fuse
• Wiring, terminals or connectors
• PCM

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0121 Lost Communication with the ABS only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the ABS and wiring harness.

Diagnostic Aids

Diagnostic Aids

• Do not install a new PSCM as part of the repair for a PSCM DTC U0121:00.
• For additional information on the messages sent to the PSCM from the ABS module, refer to the Network Message List in Section 211-02 of the workshop manual.
• The presence of DTC U0121:00 may prevent the optional steering features; active park assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Network communication concern
• ABS module

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the ABS module messages within a certain time frame. This can occur if the ABS module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 9 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0140 Lost Communication with the BCM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the BCM and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the BCM module, refer to the Network Message List in Section 211-02 of the workshop manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U140:00.

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Network communication concern
• BCM

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the ABS module messages within a certain time frame. This can occur if the ABS module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

NOTE: The serial data gateway module is also known as the GWM

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0146 Lost Communication with serial data GWM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) ) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the GWM and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the GWM module, refer to the Network Message List in Section 211-02 of the workshop manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U146:00.
• The presence of DTC U0146:00 prevents the Evasive Steering Assist (ESA) feature from activating. If the DTC sets during an assist event, the event is terminated and the assist system is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Network communication concern
• GWM

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the GWM module messages within a certain time frame. This can occur if the GWM module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

NOTE: Do not install a new PSCM as part of the repair for a PSCM DTC U151:00.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN when the ignition is ON for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0151 Lost Communication with RCM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the RCM and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the RCM module, refer to the Network Message List in Section 211-02 of the workshop manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U151:00.
• The presence of DTC U0151:00 prevents the optional Lane Centering Assist (LCA) feature from activating. If the DTC sets during an assist event, the event is terminated and the assist system is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Network communication concern
• RCM

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the RCM module messages within a certain time frame. This can occur if the RCM module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0155 Lost Communication with the IPC only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the IPC and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the IPC , refer to the Network Message List in Section 211-02 of the Workshop Manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U0155:00.

DTC Fault Trigger Conditions

Possible Sources

• Fuse
• Wiring, terminals or connectors
• IPC

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the IPC messages within a certain time frame. This can occur if the IPC wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0159 Lost Communication with the PAM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the IPC and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the PAM , refer to the Network Message List in Section 211-02 of the Workshop Manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U0159:00.

DTC Fault Trigger Conditions

Possible Sources

• Fuse
• Wiring, terminals or connectors
• PAM

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the PAM messages within a certain time frame. This can occur if the PAM wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0212 Lost Communication with the SCCM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the SCCM and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the SCCM , refer to the Network Message List in Section 211-02 of the Workshop Manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U0212:00.

DTC Fault Trigger Conditions

Possible Sources

• Fuse
• Wiring, terminals or connectors
• SCCM

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the SCCM messages within a certain time frame. This can occur if the SCCM wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

NOTE: Do not install a new PSCM as part of the repair for a PSCM DTC U023A:00.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The IPMA is integrated into the interior rear view mirror. The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U023A Lost Communication with the Image Processing Module "A" only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the IPMA and wiring harness.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the IPMA module, refer to the Network Message List in Section 211-02 of the workshop manual.
• Do not install a new PSCM as part of the repair for a PSCM DTC U023A:00.
• The presence of DTC U023A:00 may prevent the optional steering features; Evasive Steering Assist (ESA), Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Network communication concern
• IPMA

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the IPMA module messages within a certain time frame. This can occur if the ABS module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0401 Invalid Data Received from the PCM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To direct the diagnosis to the module and associated circuit sending the faulty or unknown information in the messages.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the PCM module, refer to the Network Message List in Section 211-02 of the workshop manual.
• DTC U0401:00 indicates a concern with the PCM . The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U0401:00.
• When this DTC is set, steering assist is reduced resulting in higher steering efforts during low speed maneuvers.

DTC Fault Trigger Conditions

Possible Sources

• HS-CAN concern
• One or more steering components installed incorrectly
• PCM concern

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the PCM messages within a certain time frame. This can occur if the PCM wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0415 Invalid Data Received from ABS Control Module "A" only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To direct the diagnosis to the module and associated circuit sending the faulty or unknown information in the messages.

Diagnostic Aids

Diagnostic Aids

• Steering assist may be reduced if the vehicle speed signal is missing. The module may transmit an invalid steering angle message over HS-CAN if the angle offset from ABS module is missing.
• For additional information on the messages sent to the PSCM from the ABS module, refer to the Network Message List in Section 211-02 of the workshop manual.
• DTC U0415:00 indicates a concern with the ABS . The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U0415:00.
• The presence of DTC U0415:00 may prevent the optional steering features; active park assist, Lane Keeping Assist (LKA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event is terminated and the assist feature is deactivated.

DTC Fault Trigger Conditions

Possible Sources

• HS-CAN concern
• One or more steering components installed incorrectly
• ABS module

Visual Inspection and Pre-checks

• This DTC sets when the PSCM does not receive the ABS module messages within a certain time frame. This can occur if the ABS module wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. Consult the DTC Index for additional information if needed.
• Refer to Steering GSB for additional connector and wiring inspection tips.

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 9 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.
• The SCCM uses input from several sensors and components to gather vehicle data, then sends this data to the PSCM . If the data is corrupted or invalid, the SCCM sends out "invalid", "fault" or "unknown" instead of the actual sensor data. For a list of the messages sent to the PSCM from the SCCM , refer to the Network Message List in Description and Operation in Section 211-02 of the Workshop Manual.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U0429 Invalid Data Received from the Steering Column Control Module only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the presence of DTC U0429 and identify the correct Workshop Manual section for diagnosing the DTC concern.

Diagnostic Aids

Diagnostic Aids

• DTC U0429:00 indicates a concern with the operating mode message, the torque steer compensation message or the brake pull reduction message sent from the SCCM .
• The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U0429:00.

DTC Fault Trigger Conditions

Possible Sources

• SCCM related sensors and components
• SCCM

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The serial data gateway module is also known as the GWM .
• The PSCM monitors the CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 9 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.
• The GWM uses input from several sensors and components to gather vehicle data, then sends this data to the PSCM . If the data is corrupted or invalid, the GWM sends out "invalid", "fault" or "unknown" instead of the actual sensor data. For a list of the messages sent to the PSCM from the GWM , refer to the Network Message List in Description and Operation in Section 211-02 of the Workshop Manual.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U2100 Initial Configuration not complete only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To verify the presence of DTC U0447 and identify the correct Workshop Manual section for diagnosing the DTC concern.

Diagnostic Aids

Diagnostic Aids

• DTC U0447:00 indicates a concern with the messages sent from the GWM . The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U0447:00.

DTC Fault Trigger Conditions

Possible Sources

• GWM related sensors and components
• GWM

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U045A Invalid Data Received from the PAM only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To direct the diagnosis to the module and associated circuit sending the faulty or unknown information in the messages.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the PAM module, refer to the Network Message List in Section 211-02 of the workshop manual.
• DTC U045A:00 indicates a concern with the lane information sent from the PAM . The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U045A:00.
• The presence of DTC U045A:00 may prevent the active park assist from activating. If the DTC sets during an assist event, the event may be terminated and the assist feature may be deactivated.

DTC Fault Trigger Conditions

Possible Sources

• HS-CAN concern
• PAM

Normal Operation and Fault Conditions

REFER to: Power Steering - System Operation and Component Description (211-02 Power Steering, Description and Operation).

Description

Description

• The PSCM monitors the HS-CAN when the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

Pinpoint Test Applicability

• This test applies to PSCM DTC U053B Invalid Data Received from the IPMA only. It does not apply to any other module except the PSCM .

DTC Diagnostic Strategy

DTC Diagnostic Strategy

• If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

Pinpoint Test Purpose

• To direct the diagnosis to the module and associated circuit sending the faulty or unknown information in the messages.

Diagnostic Aids

Diagnostic Aids

• For additional information on the messages sent to the PSCM from the IPMA module, refer to the Network Message List in Section 211-02 of the workshop manual.
• DTC U053B:00 indicates a concern with the lane information sent from the IPMA . The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCM DTC U053B:00.
• The presence of DTC U053B:00 may prevent the optional features; Evasive Steering Assist (ESA) and Lane Centering Assist (LCA) from activating. If the DTC sets during an assist event, the event may be terminated and the assist feature may be deactivated.

DTC Fault Trigger Conditions

Possible Sources

• HS-CAN concern
• IPMA