WOMS
B code body Medium severity

B2108 Trunk Key Cylinder Switch Failure

The OBD2 code B2108 indicates a malfunction in the trunk key cylinder switch, which may affect the operation of the trunk release mechanism

Definition

The OBD2 code B2108 indicates a malfunction in the trunk key cylinder switch, which may affect the operation of the trunk release mechanism

Common causes

  • Faulty trunk key cylinder switch
  • Wiring issues (shorts, opens, or corrosion)
  • Poor electrical connections
  • Malfunctioning body control module (BCM)
  • Mechanical obstruction in the trunk lock assembly
  • Water intrusion or moisture damage
  • Faulty key or key fob
  • Incorrect installation or alignment of the trunk lock mechanism

Common misdiagnoses

  • Faulty trunk latch
  • Malfunctioning body control module (BCM)
  • Wiring issues or shorts in the trunk circuit
  • Defective key fob or remote entry system
  • Ignition switch problems
  • Issues with the door lock actuators
  • Battery or power supply problems
  • Faulty trunk release button or switch

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context for the issue

  2. 2. Inspect the Trunk Key Cylinder

    Visually inspect the trunk key cylinder for any physical damage or signs of wear. Ensure that the key turns smoothly and that there are no obstructions

  3. 3. Test the Key Cylinder Switch

  4. 4. Disconnect the electrical connector from the trunk key cylinder switch

  5. 5. Use a multimeter to test the switch for continuity. When the key is turned to the unlock position, there should be continuity. If not, the switch may be faulty and require replacement

  6. 6. Check Wiring and Connectors

    Inspect the wiring and connectors leading to the trunk key cylinder switch for any signs of damage, corrosion, or loose connections. Repair or replace any damaged components

  7. 7. Inspect the Body Control Module (BCM)

    The BCM may be responsible for processing the signal from the trunk key cylinder switch. Check for any faults or issues with the BCM. If necessary, reprogram or replace the BCM

  8. 8. Check for Ground Issues

    Ensure that the ground connections related to the trunk key cylinder switch are secure and free of corrosion. A poor ground can lead to false readings

  9. 9. Clear the Code

    After performing the above checks and repairs, clear the trouble code using the OBD-II scanner. Then, take the vehicle for a test drive to see if the code returns

  10. 10. Seek Professional Help

    If you are unable to resolve the issue after these steps, consider consulting a professional mechanic or technician for further diagnosis and repair. By following these steps, you should be able to identify and resolve the issue related to the B2108 code