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 |
|---|---|---|---|---|
B+ Voltage Reference | B1529 03 | 1 | -- | B1529 07 |
Steering Wheel Control Switch Signal | 1 | 1 | B3622 07 | -- |
1. Steering Wheel Controls Inoperative | ||||
Circuit/System Description
The body control module (BCM) supplies voltage to the audio steering wheel control switches and monitors the return signal. Each switch state is associated to a set resistance value and when pressed a specific voltage drop occurs across the resistor unique to the switch. The BCM identifies the switch selection and activates the feature.
Conditions for Running the DTC
| • | Battery voltage is between 9-16 volts |
| • | The ignition is ON. |
Conditions for Setting the DTC
B1529 03
| • | The BCM detects a short to ground in the B+ voltage reference circuit. |
| • | The above condition is present for greater than 30 seconds. |
B1529 07
| • | The BCM detects a short to voltage in the B+ voltage reference circuit. |
| • | The above condition is present for greater than 30 seconds. |
Action Taken When the DTC Sets
The BCM will ignore switch inputs.
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | A history DTC will clear once 100 consecutive malfunction free ignition cycles have occurred. |
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
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool SWC Bank 1 status while pressing and releasing the switches. The reading should be SW1-SW10 identifying the switch pressed, and Idle when released.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the left and right steering wheel control switches.
- Ignition ON, test for B+ between the voltage reference circuit terminal 1 and ground.
- Test for B+ between the voltage reference circuit terminal 1 and the signal circuit terminals listed below:
- Ignition OFF, disconnect the X1 harness connector at the BCM.
- Test for infinite resistance between ground and the signal circuit terminals listed below:
- Ignition ON, test for less than 1 volt between ground and the voltage reference circuit terminal 5 at the left steering wheel control switch.
- Ignition ON, test for infinite resistance between ground and the voltage reference circuit terminal 5 at the left steering wheel control switch.
- Test for less than 1 ohm between the voltage reference circuit terminal 5 at the left steering wheel control switch and the voltage reference circuit terminal 5 at the right steering wheel control switch.
- If all circuits test normal, test or replace the left or right steering wheel control switch.
| ⇒ | If less than the specified value, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
| • | Steering wheel control switch signal circuit terminal 6 - left switch |
| • | Steering wheel control switch signal circuit terminal 2 - right switch |
| ⇒ | If less than the specified value, test the signal circuits for a short to voltage or an open/high resistance. If the circuits test normal, replace the BCM. |
| • | Steering wheel control switch signal circuit terminal 6 - left switch |
| • | Steering wheel control switch signal circuit terminal 2 - right switch |
| ⇒ | If less than the specified value, test the signal circuits for a short to ground. |
| ⇒ | If greater than the specified range, test the voltage reference circuit for a short to voltage |
| ⇒ | If not the specified value, test the voltage reference circuit for a short to ground. |
| ⇒ | If greater than the specified range, test the voltage reference circuit for a an open/high resistance. |
Component Testing
- Disconnect the harness connector at the right or left steering wheel control switch.
- Connect a DMM between terminal 5 and terminal 6 (left switch) or terminal 2 (right switch) of either the left or right steering wheel control switches.
| ⇒ | If any of the resistance measurements for the individual switches are not within the specified resistance values, replace the left or right steering wheel control switch. |
Function Switch | Minimum Resistance Value | Maximum Resistance Value |
|---|---|---|
Source | 787 Ohms | 987 Ohms |
No Switch Pressed | O.L. | O.L. |
Function Switch | Minimum Resistance Value | Maximum Resistance Value |
|---|---|---|
Previous | 534 Ohms | 734 Ohms |
Next | 898k Ohms | 1.25k Ohms |
Volume Up | 1.3k Ohms | 1.5k Ohms |
Volume Down | 1.6k Ohms | 1.8k Ohms |
Mute/Voice Recognition | 2.6k Ohms | 3.0k Ohms |
No Switch Pressed | O.L. | O.L. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
