GM Service Manual Online
For 1990-2009 cars only

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 Descriptor

DTC B1529 03: Control Module Voltage Reference Output 5 Circuit Low Voltage

DTC B1529 05: Control Module Voltage Reference Output 5 Circuit High Voltage

Diagnostic Fault Information

Electrical DTCs

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

12 Volt Reference

B1529 03

1

--

B1529 05

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 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

    • The system voltage is between 9 V and 16 V.
    • The ignition is ON.

Conditions for Setting the DTC

B1529 03

    • The BCM detects a short to ground in the 12 V reference circuit.
    • The above condition is present for greater than 30 seconds.

B1529 07

    • The BCM detects a short to voltage in the 12 V 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

LINK

Connector End View Reference

Component Connector End Views

Description and Operation

Steering Wheel Controls Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the X1 harness connector at the X85 Inflatable Restraint Steering Wheel Module Coil.
  2. Ignition ON, test for greater than 11 V between the voltage reference circuit terminal 5 (X1) and ground.
  3. 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 (BCM).
  4. Test for greater than 11 V between the voltage reference circuit terminal 5 (X1) and the signal circuit terminal 4 (X1).
  5. 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 (BCM).
  6. Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module (BCM).
  7. Test for infinite resistance between the signal circuit terminal 4 (X1) at the X85 Inflatable Restraint Steering Wheel Module Coil and ground.
  8. If less than the specified value, test the signal circuit for a short to ground.
  9. If all circuits test normal, test or replace the S70R Steering Wheel Control Switch - Right.

Component Testing

Static Test

  1. Disconnect the harness connector at the X85 Inflatable Restraint Steering Wheel Module Coil.
  2. Test the resistance between the terminals 4 (X1) and 5 (X1) of the X85 Inflatable Restraint Steering Wheel Module Coil.
  3. If any of the resistance measurements for the individual switches are not within the specified resistance values, replace the S70R Steering Wheel Control Switch - Right.

Function Switch

Minimum Resistance Value

Maximum Resistance Value

Volume Down

1.0 kΩ

1.4 kΩ

Volume Up

1.3 kΩ

1.7 kΩ

Seek Down

1.7 kΩ

2.1 kΩ

Seek Up

2.2 kΩ

2.6 kΩ

Source

2.8 kΩ

3.2 kΩ

Phone / Push to Talk

3.6 kΩ

4.0 kΩ

Hang Up / Audio Mute

5.1 kΩ

5.5 kΩ

No Switch Pressed

O.L.

O.L.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Steering Wheel Control Switch Assembly Replacement
    •  Control Module References for BCM replacement, setup, and programming