Circuit/System Verification
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- Ignition OFF, connect a test lamp between the HORN fuse test point and ground.
- Press and release the horn switch. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp does not illuminate or remains illuminated at all times, refer to Horn Switch Circuit Test in Circuit/System Testing .
- Ignition ON, command the horn ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp does not illuminate, test the control circuit terminal 18 at the BCM for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
- Connect a 10A fused jumper wire between B+ and the HORN fuse test point. The horns should sound and emit a clear and even tone.
- If the horn does not sound, refer to Horn Circuit Test in Circuit/System Testing .
- If the sound emitted is not clear and even, refer to Horn - Poor Tone in Circuit/System Testing .