Steering Wheel Controls Inoperative (Mute/Seek)

Steering Wheel Controls Inoperative (Mute/Seek)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provide an overview of each diagnostic category.

Circuit/System Description

The body control module (BCM) supplies voltage to the MUTE/SEEK + multiple momentary contact switch and monitors the steering wheel control 2 signal circuit. Each switch is associated to a set resistance value, when pressed a specific voltage drop occurs through a series of resistors unique to that switch. The BCM identifies the selection, then sends a serial data message that is received by the component controlled, activating the feature.

Diagnostic Aids

* This diagnostic is for the audio steering wheel controls for vehicles not equipped with RPO K59 adaptive cruise.
* Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.
* If a single switch function is inoperative, test the suspect switch. Refer to component testing.

Circuit/System Verification

Ignition ON, observe the scan tool ACC Gap Switch parameter while pressing and releasing the Mute/Seek + switches. The reading should be 2.4 volts with UP pressing Seek +, and 1.1 volts with DN pressing Mute, and inactive when released.

Circuit/System Testing

Important: It is recommended that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.

Caution: Refer to Restraint System Service Precautions.

1. Ignition OFF, disconnect the C1 harness connector at the MUTE/SEEK + switch.
2. Ignition ON, test for ignition voltage between the ignition circuit terminal 5 and ground.

• If less than the specified range, test the ignition circuit for a short to ground or open/ high resistance. If circuit test normal, and the fuse is ok, replace Run/Crank relay.

3. Test for 0 volts between the signal circuit terminal 6 and ground.

• If greater than the specified range, test the signal circuit for short to voltage. If circuit test normal, replace BCM.

4. Test for ignition voltage between the ignition circuit and the signal circuit terminal 6.

• If less than the specified range, test the signal circuit for an open/high resistance. If circuit test normal, replace BCM.

5. Ignition OFF, disconnect the C2 harness connector at the BCM.
6. Test for infinite resistance between the signal circuit terminal 57 and ground.

• If less than the specified range, test the signal circuit for short to ground. If circuit test normal, test or replace switch.

7. If all circuits test normal, test or replace the switch.

Component Testing

Caution: Refer to Restraint System Service Precautions.

1. Ignition OFF, disconnect the C1 harness connector at the MUTE/SEEK UP switch.
2. Test for infinite resistance between the signal terminal 6 and the ignition voltage terminal 5 with the switch in the open position.

• If not the specified value, replace the switch.

3. Test for less than 5500 ohms between the signal terminal and the voltage terminal with the switch closed in each position.

• If not the specified value, replace the switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

* Steering Wheel Control Switch Assembly Replacement
* Programming and RelearningProgramming and Relearning>