Diagnostic Instructions
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 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 and sets DTC B3624 when it detects a stuck Mute/Seek + 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. |
| • | The BCM module receives a clear code command from the scan tool. |
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
Connector End View Reference
Description and Operation
Steering Wheel Controls Description and Operation
Electrical Information Reference
Scan Tool Data List
Scan Tool Data List
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 in the Preface section.
- Ignition OFF, disconnect the C1 harness connector at the MUTE/SEEK + switch .
- 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. |
- 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. |
- 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. |
- Ignition OFF, disconnect the C2 harness connector at the BCM.
- 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. |
- If all circuits test normal, test or replace the switch.
Component Testing
Caution: Refer to SIR Caution in the Preface section.
- Ignition OFF, disconnect the C1 harness connector at the MUTE/SEEK + switch.
- 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. |
- 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
after completing the diagnostic procedure.
