The steering column control module (SCCM) supplies voltage to the audio steering wheel control multiple momentary contact switches and monitors the return signal. 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 SCCM identifies the selection, then sends a serial data message that is received by the component controlled, activating the feature.

Schematic Reference

Steering Wheel Secondary/Configurable Control Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Steering Wheel Controls Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the appropriate scan tool parameters for the left and right steering wheel control switches while pressing and releasing the individual switches. The scan tool parameter should change state when the switch is pressed and released.

1. Ignition OFF, disconnect the harness connector at the steering wheel control switch.
2. Ignition OFF, test for less than 2.0 ohms between the appropriate low reference circuit terminal listed below and ground.

•	right steering wheel control switch terminal 3

•	left steering wheel control switch terminal 2

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the SCCM.

3. Ignition ON, test for 4.8-5.2 volts between the appropriate signal circuit terminal listed below and ground.

•	right steering wheel control switch terminal 6

•	left steering wheel control switch terminal 1

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the SCCM.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the SCCM.

4. If all circuits test normal, test or replace the steering wheel control switch.

1. Disconnect the harness connector at the appropriate steering wheel control switch.
2. Connect a DMM between the appropriate terminals listed below of the appropriate steering wheel control switch:

•	right steering wheel control switch terminal 6 and terminal 3

•	left steering wheel control switch terminal 1 and terminal 2

⇒	If any of the resistance measurements for the individual switches are not within the specified resistance values, replace the steering wheel control switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.