DTC Descriptor
DTC B3624: Steering Wheel Controls Entertainment Signal 2 Circuit
Diagnostic Fault Information
Important: Always perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
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. |
| • | Review with the schematic when testing switch resistance values. |
| • | If a single switch function is inoperative, test the suspect switch. Refer to component testing. |
Reference Information
Schematic Reference
Steering Wheel 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
Important: Always perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
