GM Service Manual Online
For 1990-2009 cars only

Circuit 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 compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0475 -- Electric Steering Motor Circuit

Conditions for Running the DTC

    • The ignition is ON.
    • No voltage DTCs are present.

Conditions for Setting the DTC

The actual motor current does not equal the desired motor current.

Action Taken When the DTC Sets

    • DTC C0475 is stored in memory.
    • The instrument panel cluster (IPC) message center displays the PWR STR 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.

Step

Action

Yes

No

Schematic Reference: Power Steering Schematics

Connector End View Reference: Power Steering Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Inspect for poor connections at the electric power steering (EPS) motor harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 6

Go to Step 3

3

Test the EPS motor control circuits for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 6

Go to Step 4

4

Test the EPS motor control circuits for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 6

Go to Step 5

5

Replace and setup the EPS assembly. Refer to Control Module References .

Did you complete the repair?

Go to Step 6

--

6

  1. Clear the DTCs with a scan tool.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does DTC C0475 reset?

Go to Step 2

System OK