B1529

DTC B1529

Diagnostic Instructions

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

DTC Descriptors
DTC B1529 03
- Device Voltage Reference Output Circuit Voltage Below Threshold

DTC B1529 07
- Device Voltage Reference Output Circuit Voltage Above Threshold

Diagnostic Fault Information






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 Steering Wheel Secondary/Configurable Control Schematics
Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation

Steering Wheel Controls Description and Operation Steering Wheel Controls
Electrical Information Reference

* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module Referencesfor 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-SW7 identifying the switch pressed, and Idle when released.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the S70R steering wheel control switch - right.
2. Ignition ON, test for B+ between the voltage reference circuit terminal 1 and ground.

• 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 K9 body control module.

3. Test for B+ between the voltage reference circuit terminal 1 and the signal circuit terminal 2.

• If less than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 body control module.

4. Ignition OFF, disconnect the X3 harness connector at the K9 body control module.
5. Test for infinite resistance between the signal circuit terminal 2 and ground.

• If less than the specified value, test the signal circuit for a short to ground.

6. If all circuits test normal, test or replace the S70R steering wheel control switch - right.

Component Testing

1. Disconnect the harness connector at the S70R steering wheel control switch - right.
2. Connect a DMM between terminals 1and 2 of the S70R steering wheel control switch - right.

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





Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Radio and Telephone Control Switch Replacement Radio and Telephone Control Switch Replacement

Control Module References Control Module Referencesfor Body control module replacement, setup, and programming