GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 HHR 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC C0475

DTC C0475 with LNF

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 provide 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 brushless, 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 X1 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.
  3. Ignition OFF, test for less than 1.0 Ω of resistance between the control circuit terminal 3 and the control circuit terminal 1.
    4. ⇒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 2 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.
  5. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 2 and ground.
    6. ⇒If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  6. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 3 and ground.
    7. ⇒If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  7. Ignition OFF, test for greater than 1.0 MΩ of resistance between the control circuit terminal 1 and ground.
    8. ⇒If less than the specified range, test the control circuit for a short to ground. If circuits test normal, replace the power steering motor.
  8. If all circuits test normal, test or replace the PSCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Steering Column Replacement
    •  Control Module References for PSCM replacement, setup, and programming

DTC C0475 without LNF

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 power steering motor. The PSCM compares the commanded and feedback current levels to detect malfunctions in the power steering motor.

Conditions for Running the DTC
    • Engine running.
    • Power steering system voltage is 9-16 volts.
    • Steering input is present.

Conditions for Setting the DTC

A short to ground, short to voltage, or an open/high resistance in the power steering motor, or the circuits to the motor.

Action Taken When the DTC Sets
    • The driver information center (DIC) displays the POWER STEERING warning message.
    • No steering assist is provided.

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 Verification
  1. Verify DTC C0475 is not set.
    2. ⇒If the DTC is set, replace the steering column.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Steering Column Replacement