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For 1990-2009 cars only

DTC C0475 without HP5

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0475 00: Electric Steering Motor Circuit

Circuit/System Description

The power steering control module (PSCM) continuously monitors the voltage and current levels being commanded to the electric power steering (EPS) motor. The PSCM incorporates a DC amplifier that boost the voltage on the pulse width modulated (PWM) control circuits to drive the, EPS motor. The PSCM compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PSCM detects open, short to ground or short between any of the motor control circuits.

Actions Taken When DTC Sets

    • DTC C0475 is stored in memory.
    • The driver information center (DIC) displays the SERVICE POWER STEERING warning message.
    • No steering assist.

Conditions for Clearing the DTC

    • A current DTC will clear on the next malfunction free ignition cycle.
    • A history DTC will clear after 100 consecutive malfunction free ignition cycles.

Reference Information

Schematic Reference

Power Steering Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Steering System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector X5 at the PSCM.
  2. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 2 and the control circuit terminal 3.
  3. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  4. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 3 and the control circuit terminal 1.
  5. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  6. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 2 and the control circuit terminal 1.
  7. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  8. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 2 and ground.
  9. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  10. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 3 and ground.
  11. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  12. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 1 and ground.
  13. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  14. If all circuits test normal, test or replace the PSCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Power Steering Assist Motor Replacement
    •  Electronic Power Steering Motor Control Module Replacement
    •  Control Module References for PSCM replacement, setup, and programming

DTC C0475 with HP5

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC C0475 00:  Electric Steering Motor Circuit

DTC C0475 59: Electric Steering Motor Circuit / Component Protection Time-out

Circuit/System Description

C0475 00

The power steering control moduleĀ (PSCM) continuously monitors the voltage and current levels being commanded to the 3-phase steering motor. The PSCM compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.

C0475 59

The power steering control moduleĀ (PSCM) continuously monitors the thermal cycle counter of the steering gear. If the thermal cycle counter exceeds the maximum allowable limit, the steering gear has reached its end of life and must be replaced.

Conditions for Running the DTC

The ignition is ON

Conditions for Setting the DTC

C0475 00

The PSCM detects a short to ground, short to voltage, or an open/high resistance on any of the internal motor circuits.

C0475 59

The PSCM detects the thermal cycle counter has exceeded the maximum allowable limit and the whole EPS steering gear system must be replaced.

Action Taken When the DTC Sets

    • The DTC is stored in memory.
    • The driver information center (DIC) displays the POWER STEERING warning message.
    • No steering assist is provided.

Conditions for Clearing the DTC

C0475 00

    • A current DTC will clear on the next malfunction-free ignition cycle.
    • A history DTC will clear after 40 consecutive malfunction-free ignition cycles.

C0475 59

This DTC cannot be cleared

Reference Information

Schematic Reference

Power Steering Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Steering System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

C0475 00

  1. Ignition OFF, disconnect the X1 harness connector at the PSCM.
  2. Test for less than 1Ω between the ground circuit terminal 1 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 2 and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. If all circuits test normal, replace the PSCM.

C0475 59

  1. Verify that DTC C0475 59 is not set.
  2. If the DTC is set, replace the steering gear assembly

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for PSCM replacement, setup, and programming

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0475 00: Electric Steering Motor Circuit

Circuit/System Description

The power steering control module (PSCM) continuously monitors the voltage and current levels being commanded to the electric power steering (EPS) motor. The PSCM incorporates a DC amplifier that boost the voltage on the pulse width modulated (PWM) control circuits to drive the, EPS motor. The PSCM compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PSCM detects open, short to ground or short between any of the motor phase circuits.

Actions Taken When DTC Sets

    • DTC C0475 is stored in memory.
    • The driver information center (DIC) displays the SERVICE POWER STEERING warning message.
    • No steering assist.

Conditions for Clearing the DTC

    • A current DTC will clear on the next malfunction free ignition cycle.
    • A history DTC will clear after 100 consecutive malfunction free ignition cycles.

Reference Information

Schematic Reference

Power Steering Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Steering System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector X5 at the PSCM.
  2. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 2 and the control circuit terminal 3.
  3. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  4. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 3 and the control circuit terminal 1.
  5. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  6. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 2 and the control circuit terminal 1.
  7. If greater than the specified range, test the control circuits for an open/high resistance. If circuits test normal, replace the power steering motor.
  8. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 2 and ground.
  9. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  10. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 3 and ground.
  11. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  12. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 1 and ground.
  13. If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  14. If all circuits test normal, test or replace the PSCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Power Steering Assist Motor Replacement
    •  Electronic Power Steering Motor Control Module Replacement
    •  Control Module References for PSCM replacement, setup, and programming