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Low voltage at horn - half a volt

My horn quit working the other day on my '92 Bonneville. Tonight I hooked up my voltmeter to the plug that connects to the horn (two wires), and I only get about half a volt when I press the horn button. I can hear the relay clicking somewhere under the hood.

I'm guessing the next step is to find the relay and check the voltage output there. But I was wondering if anyone had encountered this problem before and had any advice.

All the horns I've dealt with previously had only one wire, and were grounded through the chassis. Am I right in guessing I should have 12v

across the two connectors in the horn plug?

Thanks,

-Ryan

Reply to
zirconx9
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Are you checking for voltage at the connecter with it unplugged from the horn? It needs to be unplugged for a proper reading. One wire is a ground (black) and the other wire is power ( green). If you connect your meter across both wires you should have 12 volts when you press the horn button. If you are getting half a volt with the connecter unplugged from the horn then you have a problem. It can be on the power or the ground side of the cicuit. A quick check would be to ground your meter at the battery negative post and check for voltage at the power side of the horn connecter. If you now have 12 volts you have a bad ground. If you still have only half a volt the problem is on the power side. I would remove the relay and inspect the terminals for corrosion. You can also check the relay socket to see if you are getting 12 volts to the relay. There will be 4 terminals in the relay socket, you should have 12 volts on 2 of them, they are both fed by the same wire.

Reply to
Mike

I was checking it at the plug, with it disconnected from the horn. I tested the ground, it was good. Then found the relay (thanks to bonnevilleclub.com for help in finding the right relay), and swaped it with another relay - success! Before I went down to buy a new relay, I put the old one back in - still works. Must have been a problem with the connections at the relay.

Thanks,

-Ryan

Reply to
zirconx9

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