FixVault

Circuit/System Testing

  1. Ignition ON, install a scan tool.
  2. Remove the horn relay.
  3. Connect a test lamp between the battery supply voltage circuit and the horn relay control circuit.
  4. Verify the test lamp turns ON and OFF when using the scan tool to command the horn relay.
    • If the test fails to illuminate, test the horn relay control circuit for a short to voltage or an open. The horn relay control circuit includes the steering wheel coil assembly and horn switch. If the circuit/connections test normal, replace the BCM.
    • If the test lamp remains illuminated at all times, test the horn relay control circuit for a short to ground. The horn relay control circuit includes the steering wheel coil assembly and horn switch. If the circuit/connections test normal, replace the BCM.
  5. If all circuits test normal, test or replace the horn relay.