WOMS
B code body Medium severity

B1810 Lamp Backup Switch Input Circuit Failure

The OBD2 code B1810 indicates a failure in the backup lamp switch input circuit, which may affect the operation of the reverse lights in a vehicle

Definition

The OBD2 code B1810 indicates a failure in the backup lamp switch input circuit, which may affect the operation of the reverse lights in a vehicle

Common causes

  • Faulty backup lamp switch
  • Damaged wiring or connectors
  • Short circuit in the circuit
  • Open circuit in the circuit
  • Corroded terminals
  • Faulty body control module (BCM)
  • Poor ground connection

Common misdiagnoses

  • Faulty backup lamp bulbs
  • Defective backup lamp relay
  • Wiring issues or shorts in the circuit
  • Malfunctioning transmission range sensor
  • Faulty body control module (BCM)
  • Incorrectly installed or damaged connectors
  • Issues with the vehicle's fuse box or blown fuses

Troubleshooting steps

  1. 1. Check the Vehicle's Manual

    Refer to the vehicle's service manual for specific information related to the B1810 code, including wiring diagrams and component locations

  2. 2. Visual Inspection

    Inspect the wiring and connectors associated with the backup lamp switch. Look for signs of damage, corrosion, or loose connections

  3. 3. Check the backup lamp bulbs to ensure they are functioning properly

  4. 4. Test the Backup Lamp Switch

    Locate the backup lamp switch, which is usually mounted on the transmission

  5. 5. Use a multimeter to test the switch for continuity. When the switch is activated (in reverse), it should show continuity. If it does not, the switch may be faulty and needs replacement

  6. 6. Check the Circuit

    Inspect the wiring harness for any breaks or shorts. Use a multimeter to check for continuity in the wiring between the switch and the power source

  7. 7. Ensure that there are no shorts to ground or open circuits

  8. 8. Inspect the Fuse

    Check the fuse related to the backup lights and the backup lamp switch circuit. If the fuse is blown, replace it and see if the code returns

  9. 9. Scan for Additional Codes

    Use an OBD-II scanner to check for any additional trouble codes that may provide more context or indicate related issues

  10. 10. Check the Body Control Module (BCM)

    If the backup lamp switch and wiring are functioning correctly, the issue may lie within the BCM. Check for any faults or issues with the BCM that could affect the backup lamp circuit

  11. 11. Clear the Code and Test Drive

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

  12. 12. Consult a Professional

    If the issue persists after following these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the B1810 code