Test L: The Steering Wheel Controls Are Inoperative/Do Not Operate Correctly

PINPOINT TEST L: THE STEERING WHEEL CONTROLS ARE INOPERATIVE/DO NOT OPERATE CORRECTLY

Normal Operation
Two different steering wheel switch configurations are available, depending on whether the vehicle is equipped with the SYNC system.

On vehicles without the SYNC system, all of the steering wheel control switches are wired to the audio control module (ACM). The steering wheel controls are: VOL+, VOL-, SEEK+, SEEK-, and MEDIA. The SEEK+ and SEEK- switches are represented by arrows.

For vehicles equipped with the SYNC system, the steering wheel controls are: VOL+, VOL-, SEEK+, SEEK-, MEDIA, VOICE, PHONE, and OK. The SEEK+ and SEEK- switches are represented by arrows, the VOICE button is represented by an icon of someone speaking, and the PHONE button is represented by an icon of a phone with an up-and-down arrow. The VOICE, PHONE, and OK switches are wired to the accessory protocol interface module (APIM), while the remaining switches are wired to the ACM.

For all switches, a reference voltage is sent from the appropriate module to the steering wheel controls. When a switch is pressed, the voltage is routed through a specific resistor value for each function. The module provides the ground for the reference voltage. The module uses this reference voltage to determine which control input function has been selected.

- DTC B1117 (Audio Steering Wheel Button Stuck) - set by the ACM or the APIM when a steering wheel control button is detected as active for greater than 120 seconds during normal operation, or for any duration during the self-test. A short to ground in any steering wheel controls circuit should not set this DTC, as the reference voltage would fall out of range, resulting in DTC B1136 (APIM) or B2404 (ACM) being set.
- DTC B1136 (Audio Steering Wheel Switch #2 Circuit Failure) - set by the APIM when the reference voltage to the steering wheel controls is out-of-range, either during normal operation or during the on-demand self-test. This can be caused by a number of failures on the steering wheel controls circuit except for a stuck button or a short to ground on circuit RME54 (WH/VT).
- DTC B2404 (Audio Steering Wheel Switch Circuit Fault) - set by the ACM when the reference voltage to the steering wheel controls is out-of-range, either during normal operation or during the on-demand self-test. This can be caused by any failure on the steering wheel controls circuit except for a stuck button or a short to ground on circuit RME24 (BU/WH).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Steering wheel controls
- Clockspring
- ACM
- APIM (if equipped)

L1-L5:

L5-L8:

L8-L10:

L11-L13: