B3624

DTC B3624

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provide an overview of each diagnostic category.



DTC Descriptor
DTC B3624
- Steering Wheel Controls Entertainment Signal 2 Circuit




Circuit/System Description

The body control module (BCM) supplies voltage to the MUTE/SEEK + multiple momentary contact switch and monitors the steering wheel control 2 signal circuit. Each switch state is associated with a set resistance value and when the switch is pressed, a specific voltage drops across the resistor unique to that switch. The BCM identifies the selection and sets DTC B3624 when it detects a stuck switch.


Conditions for Running the DTC

Ignition is in RUN.


Conditions for Setting the DTC

Steering wheel controls 2 signal circuit remains in the same state for 1 minute.


Action Taken When the DTC Sets

MUTE/SEEK + switch remains in the last selected position.


Conditions for Clearing the DTC

* The DTC becomes history when the fault is no longer present.
* A History DTC clears after 100 malfunction free ignition cycles.



Diagnostic Aids

* This diagnostic is for the audio steering wheel controls for the vehicle not equipped with RPO K59 adaptive cruise.
* Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.
* 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 (Steering Wheel Secondary/Configurable Control Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

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

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Data List

Control Module References (Programming and Relearning)


Circuit/System Verification

Ignition ON, observe the scan tool ACC Gap Switch parameter while pressing and releasing the Mute/Seek + switches. The reading should be 2.4 volts with UP pressing Seek +, and 1.1 volts with DN pressing Mute, and inactive when released.


Circuit/System Testing

Important: It is recommended that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.


Caution: Refer to SIR Caution (SIR Caution) .

1. Ignition OFF, disconnect the X1 harness connector at the MUTE/SEEK + switch .
2. Ignition ON, test for ignition voltage between the ignition circuit terminal 5 and ground.

• If less than the specified range, test the ignition circuit for a short to ground or open/ high resistance. If circuit test normal, and the fuse is ok, replace Run/Crank relay.

3. Test for 0 volts between the signal circuit terminal 6 and ground.

• If greater than the specified range, test the signal circuit for short to voltage. If circuit test normal, replace BCM.

4. Test for ignition voltage between the ignition circuit and the signal circuit terminal 6.

• If less than the specified range, test the signal circuit for an open/high resistance. If circuit test normal, replace BCM.

5. Ignition OFF, disconnect the X2 harness connector at the BCM.
6. Test for infinite resistance between the signal circuit terminal 57 and ground.

• If less than the specified range, test the signal circuit for short to ground. If circuit test normal, test or replace switch.

7. If all circuits test normal, test or replace the switch.



Component Testing
Caution: Refer to SIR Caution (SIR Caution) .

1. Ignition OFF, disconnect the X1 harness connector at the MUTE/SEEK + switch.
2. Test for infinite resistance between the signal terminal 6 and the ignition voltage terminal 5 with the switch in the open position.

• If not the specified value, replace the switch.

3. Test for less than 5500 ohms between the signal terminal and the voltage terminal with the switch closed in each position.

• If not the specified value, replace the switch.




Repair Instructions

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

* Steering Wheel Control Switch Assembly Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming