GM Service Manual Online
For 1990-2009 cars only

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.

Circuit/System Description

The heated steering wheel control module controls the heated steering wheel and the heated steering wheel on indicator based on an input from the heated steering wheel switch. When the heated steering wheel switch is pressed, the switch signal circuit is pulled to ground. This indicates to the heating steering wheel control module that steering wheel heat is requested. When the request is seen, the heat steering module supplies voltage to the indicator lamp and supplies voltage to the heating elements, which are internal to the module.

Reference Information

Schematic Reference

Steering Wheel Schematics

Connector End View Reference

Steering Wheel and Column Connector End Views

Description and Operation

Steering Wheel and Column Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Waterleak Test Preparation

Circuit/System Verification

Ignition ON, press and release the heated steering wheel switch. The heated steering wheel indicator should illuminate and the left and right sides of the steering wheel should become warm.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the heated steering wheel control module.
  2. Ignition OFF, test for less than 1.0 ohm of resistance between the ground circuit terminal D and ground.
  3. If greater than the specified value, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal A and ground.
  5. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  6. Install a 3A fused jumper wire between the control circuit terminal C and B+. Verify the heated steering wheel indicator is illuminated.
  7. If the indicator does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the left steering wheel control switch.
  8. Install a test lamp between the supply voltage circuit terminal B and B+.
  9. Cycle the heated steering wheel switch. The test lamp should turn ON and OFF when changing between the commanded states.
  10. If the test lamp is always ON, test the supply voltage circuit for a short to ground. If the circuit tests normal, test or replace the left steering wheel control switch.
    If the test lamp is always OFF, test the supply voltage circuit for a short to voltage or and open/high resistance. If the circuit tests normal, test or replace the left steering wheel control switch.
  11. If all circuits test normal, replace the heated steering wheel control module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Steering Wheel Control Switch Assembly Replacement
    •  Inflatable Restraint Steering Wheel Module Coil Replacement
    •  Control Module References for heated steering wheel control module replacement, programming, and setup