B3622

DTC B3622

DTC Descriptor

DTC B3622 07

Steering Wheel Controls Signal Circuit

Diagnostic Fault Information

Important:
Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

Circuit/System Description
The body control module (BCM) supplies 12 volts to the audio steering wheel control multiple momentary contact switches and monitors the steering wheel controls signal circuit. 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
Ignition ON

Conditions for Setting the DTC
BCM detects voltage higher than normal

Action Taken When the DTC Sets
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.

Reference Information

Schematic Reference
Steering Wheel Schematics

Connector End View Reference
^ Steering Wheel and Column Connector End Views
^ Computer/Integrating Systems Connector End Views

Electrical Information Reference
^ Circuit Testing
^ Connector Repairs
^ Testing for Intermittent Conditions and Poor Connections
^ Wiring Repairs

Circuit/System Testing

Caution:
Refer to Restraint System Caution.

1. Ignition OFF, disconnect the harness connector at the audio steering wheel control switch.
2. Ignition ON, connect a test lamp between the steering wheel controls signal circuit and ground at the switch harness connector and verify it does not illuminate.
^ If test lamp illuminates, test the signal circuit for short to voltage. If circuit tests normal, replace the BCM.
3. If circuits tests normal, test or replace the switch.

Component Testing

Caution:
Refer to Restraint System Caution.

1. Ignition OFF, disconnect the harness connector at the audio steering wheel control switch.
2. Test the switch for infinite resistance between the remote radio control supply voltage terminal and the steering wheel controls signal terminal with the switch in the open position.
^ If less than infinite resistance, replace the switch.
3. Test resistance values between the supply voltage terminal and the signal terminal with the switch closed in each position and verify readings are approximate to what the schematic reads.
^ If values do not, replace the switch.

Repair Instructions

Important:
Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

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