Horn Relay Troubleshooting

Re: Horn Relay Troubleshooting
Posted By: Dick S. Moore (crdn-ippool-115.grm.net)
Date: 8/17/2000, 9:57 a.m.

Reply To: Re: Two Easy Electrical Questions (Joe Rivituso)

The easy way to diagnose your horn problem. There`s a horn relay on the driver`s side under the hood below the master brake cylinder. It should have three terminals numbered 1, 2, &3.

#1 terminal should have +12V (to ground)

#2 terminal goes to the horn button, the horn button grounds this wire when depressed.

#3 terminal goes to the horn(s), and recieves +12V when the relay closes.

A jumper from #1 to #3 terminal will honk the horns if there is +12V there, and if the horns are OK.

A jumper from terminal #2 to ground will close the relay and honk the horns if the relay is good and the above scenario works.

If all the above prove OK the wire from the horn botton is not sending a ground to the relay.

Bulkhead connector dirty or corroded? Horn button not grounding the #2 wire? Last, an open wire? not likely, but possible.

The NAPA # for the relay if it proves bad is HR113

Dick S. Moore

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