Heated Steering Wheel Malfunction

Heated Steering Wheel Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (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 heated steering wheel control module supplies voltage to the indicator lamp and supplies voltage to the heating elements, which are internal to the steering wheel.

Reference Information
Schematic Reference

Steering Wheel Schematics (Steering Wheel Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Steering Wheel and Column Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

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. Test for less than 5.0 ohm between ground terminal 1 and ground.

• If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition ON, verify a test lamp illuminates between B+ terminal 4 and ground.

• If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

4. Ignition OFF, connect a test lamp between signal circuit terminal 3 and B+. Place the heated steering wheel switch in the OFF position.

• If the test lamp illuminates, test the signal circuit for a short to ground, If all circuits test normal, test or replace the heated steering wheel control switch.

5. Connect a test lamp between signal circuit terminal 3 and B+. Place the heated steering wheel switch in the ON position.

• If the test lamp does not illuminate, test the signal circuit for a short to voltage or open/high resistance and test the ground circuit for an open/high resistance. If all circuits test normal, test or replace the heated steering wheel control switch.

6. Verify that a test lamp does not illuminate between control circuit terminal 7 and ground.

• If the test lamp illuminates, test for a short to voltage on the heated steering wheel element control circuit.

7. Test the heating element resistance between control circuit terminal 7 and ground using the appropriate RPO code values:

* NR7: 1.5-2.0 ohm
* N30/N50: 0.6-0.9 ohm

• If not within the specified range, test the heating element control circuit for a short to ground or open/high resistance and the ground circuit for an open/high resistance. If all circuits test normal, replace the heated steering wheel.

8. Verify that a test lamp does not illuminate between signal circuit terminal 5 and ground.

• If the test lamp illuminates, test for a short to voltage on the heated steering wheel element signal circuit.

9. Test for 6000-35000 ohm between signal circuit terminal 5 and ground.

• If not within the specified range, replace the heated steering wheel.

10. If all circuits test normal, replace the heated steering wheel control module.

Component Testing

Heated Steering Wheel Control Switch
1. Place the heated steering wheel control switch in the OFF position.
2. Test for infinite resistance between terminal 2 and terminal 8.

• If less than the specified value, replace the switch.

3. Place the heated steering wheel control switch in the ON position.
4. Test for less than 2 ohm between terminal 2 and terminal 8.

• If greater than the specified value, replace the switch.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Steering Wheel Control Switch Assembly Replacement (Service and Repair)
* Steering Wheel Inflatable Restraint Module Coil Replacement (Removal and Replacement)
* Control Module References (Programming and Relearning)for heated steering wheel control module replacement, programming, and setup