GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The power steering control module (PSCM) monitors the temperature of the Power Steering System. The PSCM uses voltage, current levels and input from an internal temperature sensor to calculate an estimated system temperature. If the PSCM detects a high system temperature event is occurring, the amount of assist is reduced to lower system temperature to prevent thermal damage to the power steering components.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0176 System Thermal Error

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

DTC Symptom

DTC Symptom Descriptor

54

Temperature High

Condition for Running the DTC

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

Conditions for Setting the DTC

The PSCM detects a high system temperature.

Action Taken When the DTC Sets

    • DTC C0176 54 is stored in memory.
    • Steering assist is reduced.

Conditions for Clearing the DTC

    • A current DTC will clear when the Power Steering System temperature returns to normal.
    • A history DTC will clear after 100 consecutive malfunction-free ignition cycles.
    • Using a scan tool

Diagnostic Aids

    • DTC C0176 54 does not indicate that a malfunction has occurred. Rather that the PSCM had to limit current to the power steering motor to avoid thermal damage to the Power Steering System components.
    • Inspect the under dash area around the steering column assembly. Ensure that no other components have come in contact with the power steering motor and module assembly, such as under dash insulation, or other electrical components.
    • Ensure that no steering components down stream of the power steering column assembly, such as ball joints, tie rod ends, universal joints, or the steering gear assembly, are mechanically binding.

Test Description

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

  1. This step tests if the high system temperature is driving condition related.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Since most occurrences of the DTC are caused by excessive static steering, such as parking maneuvers and high ambient temperatures, review the Power Steering System with the customer to determine the conditions under which the DTC set.

Did steering conditions and/or high ambient temperatures cause the DTC to set?

Go to Step 3

Go to Diagnostic Aids

3

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within normal conditions.

Does the DTC reset?

Go to Step 2

System OK