WOMS
B code body Medium severity

B1520 Hood Switch Circuit Open

The OBD2 code B1520 indicates that there is an open circuit in the hood switch, which is responsible for detecting whether the hood is closed or open

Definition

The OBD2 code B1520 indicates that there is an open circuit in the hood switch, which is responsible for detecting whether the hood is closed or open

Common causes

  • Faulty hood switch
  • Damaged wiring or connectors
  • Corroded terminals
  • Open circuit in the wiring harness
  • Poor ground connection
  • Malfunctioning body control module (BCM)

Common misdiagnoses

  • Faulty hood latch
  • Bad hood switch
  • Wiring issues or shorts
  • Body control module (BCM) failure
  • Faulty alarm system
  • Incorrectly installed aftermarket accessories
  • Battery or power supply issues

Troubleshooting steps

  1. 1. Visual Inspection

    Check the Hood Switch: Locate the hood switch and inspect it for any visible damage, corrosion, or disconnection

  2. 2. Wiring Inspection

    Examine the wiring and connectors leading to the hood switch for fraying, breaks, or loose connections

  3. 3. Test the Hood Switch

    Multimeter Test: Use a multimeter to test the continuity of the hood switch. With the hood closed, the switch should show continuity (closed circuit). When the hood is open, it should show no continuity (open circuit)

  4. 4. Switch Operation

    Manually operate the switch to ensure it is functioning correctly

  5. 5. Check for Faulty Connections

    Connector Inspection: Ensure that all connectors related to the hood switch are secure and free of corrosion

  6. 6. Ground Connections

    Check the ground connections for the hood switch circuit to ensure they are clean and secure

  7. 7. Inspect Related Components

    Body Control Module (BCM): If the hood switch is part of a larger system controlled by the BCM, check for any faults in the BCM

  8. 8. Fuses

    Check the relevant fuses associated with the hood switch circuit to ensure they are not blown

  9. 9. Scan for Additional Codes

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

  10. 10. Clear Codes and Test Drive

    Clear Codes: After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner

  11. 11. Test Drive

    Take the vehicle for a test drive to see if the code reappears

  12. 12. Professional Diagnosis

    If you are unable to resolve the issue, consider seeking help from a professional mechanic who can perform more advanced diagnostics. By following these steps, you should be able to identify and resolve the issue related to the B1520 code