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. |
DTC Descriptors
DTC B1529 03: Device Voltage Reference Output Circuit Voltage Below ThresholdDTC B1529 07: Device Voltage Reference Output Circuit Voltage Above Threshold
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Remote Radio Control Supply Voltage | B1529 03 | B1529 03 | B1529 07 | -- |
Remote Radio Control Signal | 1 | 1 | 1 | -- |
1. Steering Wheel Controls Inoperative | ||||
Circuit/System Description
The body control module (BCM) 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 BCM identifies the selection, then sends a serial data message that is received by the component controlled, activating the feature.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
B1529 03
The BCM senses the reference voltage above witch voltage that is below 9.5 volts.
B1529 07
The BCM senses the reference voltage above witch voltage that is above 16 volts.
Action Taken When the DTC Sets
The BCM will ignore the switch command.
Conditions for Clearing the DTC
| • | A current DTC clears when the malfunction is no longer present. |
| • | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction. |
Diagnostic Aids
| • | This diagnostic is for the audio steering wheel controls. |
| • | Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly. |
| • | Review schematic when testing switch resistance values. |
| • | If a single switch function is inoperative, test the suspect switch. Refer to component testing. |
Reference Information
Schematic Reference
Steering Wheel Secondary/Configurable Control Schematics
Connector End View Reference
Description and Operation
Steering Wheel Controls Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Ignition ON, observe the scan tool SWC Bank 1 status while pressing and releasing the switches. The reading should be SW1-SW7 identifying the switch pressed, and Idle when released.
Circuit/System Testing
Important: It is recommended that component testing is performed before circuit testing when diagnosing steering wheel controls.
- Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
- Ignition ON, test for ignition voltage between the ignition circuit terminal 3 and ground.
- Test for the 0 volts between the signal circuit terminal 4 and ground.
- Test for ignition voltage between the ignition circuit terminal 3 and the signal circuit terminal 4.
- Ignition OFF, disconnect the harness connector at the BCM.
- Test for infinite resistance between the signal circuit terminal and ground.
- If all circuits test normal, test or replace switch.
| ⇒ | If less than specified value, test the ignition circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM. |
| ⇒ | If greater than specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
| ⇒ | If less than specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. |
| ⇒ | If less than specified value, test the signal circuit for a short to ground. |
Component Testing
- Ignition OFF, disconnect the harness connector at the suspect steering wheel control switch.
- Test for infinite resistance between the ignition terminal 3 and the signal terminal 4 with the switch in the open position.
- Test for less than 5400 ohms of resistance between the signal terminal 4 and the ignition terminal 3 with the switch in the closed position.
| ⇒ | If less than specified value, replace the switch. |
| ⇒ | If greater than the specified value, replace the steering wheel control switch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
