Where do i find the horn relay ona 1988 monte carlo ?

Find a facility with a scan tool that can access the Body Control Module. They will need to look at the data. Ideally the scan tool will have bi-directional control. You should be able to watch the horn be pressed via the scan tool in the Body Control Module. If you can see it is pressed, but no horn sound, try to operate the horn via the scan tool. GM supports this functionality test. If the horn does not operate, check the horn relay. It could be a broken wire between the BCM and the fuse box, or between the horn contact switch and the BCM.

Sort of tucked under the dash on the left. Kind of hard to explain but there is a section on the firewall as the main fuse block and there is another section attached to the backside of dash kinda just above the parking brake release handle. I think you will find your "convenience center" although I find that to be a very inconvenient spot! So before going through all this I might suggest just taking the connections off the horn itself and lightly sanding to make sure you have good connection first. Always start with the easiest and most inexpensive. Best of luck.

it should be in the fuse box.

do you hear a click sound from a relay when pressing on horn button? most likely is underhood. if so,locate the horn(s) and test voltage with a test light or DVOM at the horn + side. if both have voltage,check - side.(ground).if both are correct replace both horns.

HORN RELAY IS IN THE FUSE BOX UNDER THE INSTRUMENT PANEL NEXT TO STEERING COLUMN.

When repairing you cars timing chain , remember to research your cars firing order before you start . You can pick up a mechanical car model book at your local parts dealer . More? ChaCha.

the horn has a 15 amp fuse, there is also a horn relay.

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Hope this helps.

make sure you check horn fuse and relay. Let me know

fuse, horn wires to the horn or switch in sterring wheel