GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Equinox 🢒 Power and Signal Distribution 🢒 Wiring Systems and Power Management 🢒 DTC C0475

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.

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