BMC and horn
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BMC and horn
2005 Chevy Impala....
The horn doesn't work. When jumping the relay the horn works. Which color wire runs from the back off the fuse box to the BCM? I'm hopeful that there is just a bad wire somewhere.
The horn doesn't work. When jumping the relay the horn works. Which color wire runs from the back off the fuse box to the BCM? I'm hopeful that there is just a bad wire somewhere.
CF Active Member
Joined: Feb 2012
Posts: 262
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From: West PA
The problem may be in the steering wheel clock-spring. Do you have the alarm button on the key fob? Test the BCM to relay connection by activating the alarm or a door-lock "chirp". The steering wheel buttons are wired directly to the relay, the BCM only activates the horn for alarm or chirp functions.
The horn relay wire color is black, when grounded the relay closes, sounding the horn. The wire will have 12V when measured with the relay plugged-in, unplug the relay and the 12V should go to zero (unless the BCM injects some stray voltage).
Good luck, let us know what you find.
The horn relay wire color is black, when grounded the relay closes, sounding the horn. The wire will have 12V when measured with the relay plugged-in, unplug the relay and the 12V should go to zero (unless the BCM injects some stray voltage).
Good luck, let us know what you find.