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 is always ON or always OFF, refer to Horn Switch Circuit Test .
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 harness connector X5 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
Connect a 15 A fused jumper wire between the HORN fuse test point and B+. The right horns should sound and emit a clear and even tone.
- If the horns do not sound, refer to Right Horn Circuit Test .
- If the sound emitted is not clear and even, refer to RIGHT HORN - Poor Tone .
Connect a 20 A fused jumper wire between the HDLMP WASH fuse test point and B+. The left horn should sound and emit a clear and even tone.
- If the left horn does not sound, refer to Left Horn Malfunction .
- If the sound emitted is not clear and even, refer to LEFT HORN - Poor Tone .