Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Have you tried checking for voltage at the horn when the switch is depressed (green wire)? If you have voltage there, then the problem is the horn. If no voltage, check for a relay that works the horn in the convinence center, where the turn signal flasher is located. It will be square and a couple of inches big. Sorry, can't remember the color want to say green or white. There may be another relay there that works the key buzzer, you could identify this one by leaving the key off and in the switch so the buzzer sounds and then feel for the relay that is buzzing, thus eliminating it as the horn relay. Check for voltage to the relay. Also to check the horn switch on the steering wheel, hook a volt meter or test light to 12 volts and check the black wire that goes up the steering column in the turn signal switch harness for ground. Putting power into the wire, or using it for ground, when you push the horn switch you should get 12 volts or the test light should come on as the horn switch grounds the circuit to energize the relay to put voltage to the horn.
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