GM Service Manual Online
For 1990-2009 cars only

DTC C0475 Symptom 00

Circuit 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.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0475 Electric Steering Motor Circuit

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

00

No Additional DTC Information

Conditions for Running the DTC

    • The ignition is ON, with the engine ON.
    • 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 in the power steering motor, or the circuits to the motor.

Action Taken When the DTC Sets

    • A DTC C0475 00 is stored in memory.
    • The 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.
    • Using a scan tool

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool, select Diagnostic Trouble Codes (DTC) function.

Does the scan tool indicate that DTC C0475 00 is current?

Go to Step 3

Go to Step 4

3

Replace the power steering motor and module assembly. Refer to Power Steering Assist Motor Replacement .

Did you complete the repair?

Go to Step 3

--

4

  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK

DTC C0475 Symptom 64

Circuit Description

The power steering control module (PSCM) continuously monitors the position of the power steering motor. The PSCM uses the motor position data to determine if a loss of mechanical coupling has occurred between the motor and the steering column shaft.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0475 Electric Steering Motor

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

64

Actuator Slipping

Conditions for Running the DTC

    • The ignition is ON, with the engine ON.
    • Power Steering System voltage is 9-16 volts.
    • Steering input is present.

Conditions for Setting the DTC

The PSCM detects a motor position value that exceeds the mechanical travel limitation of the system, or more than 4.5 steering wheel revolutions.

Action Taken When the DTC Sets

    • A DTC C0475 64 is stored in memory.
    • The driver information center (DIC) displays the POWER STEERING warring 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.
    • Using a scan tool

Diagnostic Aids

If the intermediate shaft, or the steering gear coupler is disconnected during a previous repair, and the steering wheel is turned more than 4.5 revolutions with the engine ON, DTC C0475 64 will set.

Test Description

The number below refers to the step number on the diagnostic table.

  1. Tests if the malfunction is in the power steering motor/module assembly, or in the steering column assembly.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool monitor the DTC information for DTC C0475 64.

Does the scan tool indicate that DTC C0475 64 is current?

Go to Step 3

Go to Diagnostic Aids

3

  1. Separate the power steering motor/module assembly from the steering column. Refer to Power Steering Assist Motor Replacement .
  2. Inspect the rubber coupling for separation, or damage.

Did you find any damage to the rubber coupling?

Go to Step 4

Go to Step 5

4

Replace the power steering motor/module assembly. Refer to Power Steering Assist Motor Replacement .

Did you complete the repair?

Go to Step 6

--

5

Replace the steering column assembly. Refer to Steering Column Replacement .

Did you complete the replacement?

Go to Step 6

--

6

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK