WOMS
B code body Medium severity

B1351 Ignition Key-In Circuit Short To Battery

The OBD2 code B1351 indicates a malfunction in the ignition key-in circuit, specifically a short to battery, which means that the circuit detecting whether the ignition key is in the ignition switch is receiving an...

Definition

The OBD2 code B1351 indicates a malfunction in the ignition key-in circuit, specifically a short to battery, which means that the circuit detecting whether the ignition key is in the ignition switch is receiving an unintended voltage from the battery

Common causes

  • Shorted wiring in the ignition key-in circuit
  • Faulty ignition switch
  • Damaged connectors or terminals
  • Corroded wiring
  • Malfunctioning body control module (BCM)
  • Improperly installed aftermarket accessories
  • Faulty key-in switch or sensor

Common misdiagnoses

  • Ignition switch failure
  • Faulty ignition lock cylinder
  • Shorted wiring harness
  • Defective body control module (BCM)
  • Malfunctioning keyless entry system
  • Battery issues
  • Faulty relays or fuses
  • Problems with the anti-theft system
  • Incorrectly installed aftermarket accessories
  • Grounding issues

Troubleshooting steps

  1. 1. Check the Vehicle's Manual

    Refer to the vehicle's service manual for specific information related to the B1351 code and the ignition key-in circuit

  2. 2. Visual Inspection

  3. 3. Inspect the ignition switch and surrounding wiring for any visible damage, corrosion, or loose connections

  4. 4. Check the wiring harness for any signs of wear, fraying, or shorting against metal surfaces

  5. 5. Test the Ignition Switch

  6. 6. Use a multimeter to test the ignition switch for proper operation. Ensure that it is functioning correctly and that the contacts are not stuck or damaged

  7. 7. Check for Shorts

  8. 8. Inspect the wiring in the key-in circuit for any shorts to battery voltage. This may involve checking the continuity of the wires and ensuring they are not touching any other wires or metal surfaces

  9. 9. Inspect the Key Cylinder

  10. 10. If applicable, check the key cylinder for any issues. Sometimes, a malfunctioning key cylinder can cause problems with the key-in circuit

  11. 11. Scan for Additional Codes

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

  13. 13. Check Fuses

  14. 14. Inspect the fuses related to the ignition and security systems. A blown fuse can sometimes cause circuit issues

  15. 15. Test the Body Control Module (BCM)

  16. 16. If the ignition switch and wiring are functioning correctly, the issue may lie within the BCM. Test the BCM for proper operation and check for any software updates or recalls

  17. 17. Clear the Code

  18. 18. 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

  19. 19. Consult a Professional

  20. 20. If the issue persists after performing 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 B1351 code