Help! 1992 corvette horn not working

[Jessica19699]

hello CAC viewer's I have a question I hope someone can help me with i just took my 1992 corvette to have it inspected and the guy told me the horn doesn't work and It failed. What would cause it not to work and how would you test and fix this. Can anyone help or dealt with this before is there a fuse I can check ?

 

[ecss]

hello CAC viewer's I have a question I hope someone can help me with i just took my 1992 corvette to have it inspected and the guy told me the horn doesn't work and It failed. What would cause it not to work and how would you test and fix this. Can anyone help or dealt with this before is there a fuse I can check ?

The Theft fuse powers the horns and horn relay. It's located on a fuse panel under the passenger side dash above the footwell area inside the vehicle. The horn relay is also located in the same area. If you don't hear the relay click in either of the test below the fuse could be blown. If you do hear the relay click the fuse is good.

When you press on either horn button do you hear a faint click every time you press the switch from under the glove box area?

If you do, that would indcate the problem is most likely bad horns. The two horns are located under the hood one on each side of the radiator area bolted to the frame rails.

I believe each horn has two wires going to it. A ground wire and the signal wire (12 volts). If you unplug the signal wire and press on the horn button you should measure 12 volts on that disconnected wire. Also verify the ground wire is grounded.

If you don't hear the relay click each time you press the horn button you can test the horn this way.

Open the driverside door. Security light on the dash should blink.
Roll the driverside window down.
Lock the doors using the power door lock switch.
Security light on the dash should go solid.
Get out of the car and close the drivers door.
Reach in and manually open or use the power door lock switch and open the door.
The factory alarm should sound and the horns should pulse on and off.
Use the door lock key and turn the key to unlock the door and the alarm should reset.

If that works, the problem is probably both horn switch buttons or the horn switch the horn buttons press down on are broken. As far as I know the parts are no longer available.

With a small jewelers screwdriver carefully pry off one of the horn button switches. The back side of the switch has a pin that pushes down on the switch. If the pin on the back side of the switch is broken, just leave the switch off and activate the switch with your finger to pass inspection.
Used switches are on Ebay but in the $50 range per switch. :eyerole If it's the switch contacts I don't see any one selling them for a 92. Appears Ecklers, Zip Corvette and MidAmerica sell switches for a 94-96.

Here's a picture of one of the horn buttons. You can see two of the locking tabs on the left.
I've never pryed one off so if you attempt to remove one, be very careful.

 

[Jessica19699]

ecss, thanks again for your replies you have been a great help to me.my boyfriend checked the fuses for theft under the foot well area hell he checked them all and none looked blown ,he said he checked the relays to by swapping them around and still nothing he said he never heard a click when he took the wires off the horn, but then again he is a little hard of hearing lol (I will check the alarm when I get home today like you suggested just to make sure), we took the car down to a local mechanic I use a lot for repairs and he took off the horn wires and put a light tester on it and when we pressed the button it lit up he also had some device he used to check the grounding and when we pressed on the button it showed as being grounded correctly, he told me the horn itself is bad. so I hope he is correct cause I just ordered 2 of them last night I figured I would replace them both cause if one is bad now what's to say the other wont go bad soon if not now also. Does his diagnoses sound correct to you? thanks again for your help you seem to be one of the only ones on here offering advice

p.s-does all the car alarm sound come from the horns or is there another device that sounds along with the horns, the car has an aftermarket alarm system installed on it also.

 

[hcbph]

I'm no wiring expert but I have had some issues before relating to horns on non Corvettes. On other vehicles I was able to test them by making up a test wire that was nothing more than a alligator clip that clipped onto the end of the positive cable of the battery, a momentary switch wired in the middle and a spade connector on the other end compatible with the connector on the horn. I also wired in a small fuse into it between the alligator clip and the switch as a just-in-case, so I wouldn't burn anything up by accident. This is for a negative ground horn test.

Unhook the existing wire to the horn, connect up the spade connector in it's place. Clip the alligator clip to the positive cable end at the battery. Press the momentary switch and see if the horn honks or not. If it does, the horn is likely good assuming it has a good ground to it. If it doesn't, the horn is likely bad.

One vehicle I tested had a bad horn, but usually if there are 2 horns at least one will work and the other won't if one is bad. If neither horn works then it was start tracing the wiring. Find the horn relay and check it with a Digital Volt Meter and see if there's voltage at the relay when the horn button is pressed on the steering wheel. If there is voltage, then start using an ohm meter and start tracing and checking out the wiring for a break in the wiring.

Remember a relay is typically 2 sets of input. One is a 12 volt source that's hot all the time and the output that goes to the horn. The other I assume would be the wiring from the horn button that energizes the relay to activate the horn along with a ground wire for the 12 v from the horn button.

If you have a FSM, that's the best source of info and a schematic on your wiring.

Hope that helps. Good luck.

 

[Jessica19699]

hcbph, thanks for the info I will check into this

 

[hcbph]

Jessica

Here's a thought. You need a horn to pass inspection, far as I know nothing says it has to be on the steering column. It that's true and the horns work, nothing says (AFAIK) you can't rig up something like the test wire I mentioned and put the button inside the car temporarily. Find some way to work the wire inside and tape it down somewhere temporarily.
Get your inspection done then find and fix your issue as you have the time to track it down.

Many years back I had an old Dodge pickup I had to do that to and it worked. Don't live where there's inspections any more so it's not an issue here plus that truck is long gone.

Paul

 

[ecss]

If the mechanic used a test light and the light came on when the horn button was depressed and no sound from the honrs that indicates the horns are bad.

The horns are made of metal and the insides of them rust out and is a very common problem.

The horn relay is controlled by two different sources.
1) The horn buttons on the steering wheel
2) The Central Control Module to set off the alarm.

I installed plastic horns made by PIAA. I did have to modify the wire connections at the new horns.

Note: Each horn has a different sound to it and so they are not the same. I think for the factory horns, one of them sounds a A note and the other one is a C note.

 

[Jessica19699]

ECSS, yeah that's what the mechanic said they rust out from the elements and the car sitting so low to the ground, like I said I bought 2 new ones (pretty sure they are metal) and I hope that does the trick it looks like I might have to modify the connection on them also from what I got on the car now. Any ideas or insight on what I should do to modify the wire to fit the new horns? it looks like 2 male prongs on the new horn and the old horn has a plug you plug into the horn. Thanks again to both you guys for your replies.

 

[ecss]

ECSS, yeah that's what the mechanic said they rust out from the elements and the car sitting so low to the ground, like I said I bought 2 new ones (pretty sure they are metal) and I hope that does the trick it looks like I might have to modify the connection on them also from what I got on the car now. Any ideas or insight on what I should do to modify the wire to fit the new horns? it looks like 2 male prongs on the new horn and the old horn has a plug you plug into the horn. Thanks again to both you guys for your replies.

When you get the horns, take one of them with you to any auto part store and get some female crimp connector lugs. Ask the counter person to verify what size female crimp connector lug will fit. You can cut off the original plug. Strip some wire back and use pliers to crimp the new connectors onto the wires.

If the new horns have + or - markings for each terminal you need to verify the 12 volt wire goes to the + terminal and the ground wire to the - terminal lug. If no markings it doesn't matter which wire goes to which terminal on the new horns.

The hardest part will probably be finding a way to mount the new horns since they are usually a universal fit.

Here's a picture of a female crimp connectors.

 

[Jessica19699]

ecss ,hey thanks again for all your help, I will do that when I receive them .I will repost and let you know how it turns out

 

[Jessica19699]

ecss, question when it comes to my horn wire there are 2 wires connected to the connector a black and green one I'm assuming the green is the ground and the black is hot? Also the replacement horns I got are 2 prong like I said before they aren't marked positive and negative it says to connect a jumper wire(which came with the horn) to one of the terminals and then connect that to the mounting screw of the horn and mount it to the car ,the other switch wire coming from the horn goes to the other prong, so if that is the case what do I do with the green wire of the original wire hook up to the connector would I not use the connector wire and just strip out the original black and green wires from the car and use them both? any ideas

 

[Jessica19699]

would I just scrap the jumper wire that came with the horn and use the black and green one from the car on both connectors?

 

[ecss]

would I just scrap the jumper wire that came with the horn and use the black and green one from the car on both connectors?

The Green wire is 12 volts when the horn button is pressed.
The Black wire is ground.

Use the two factory wires.
Cut the factory plug off.
Install new female terminal lugs on both wires.
Plug Green wire to one lug of the new horn.
Plug Black wire to the other lug.
Makes no difference which terminal lug you use on your new horn.

If you were to follow the Black factory wire it would bolt to the frame rail for each horn so that actually is the ground wire for the factory horns.

If you were to manually ground the factory Green wire, the Theft fuse would blow as soon as the horn button is pressed.ad

 

[Jessica19699]

aww wow ok thanks I'm glad I checked with you, I will try that and let you know how it turns out thanks again

 

[Jessica19699]

one last thing do I need to disconnect the battery before doing this to the wires or does it not matter?

 

[ecss]

one last thing do I need to disconnect the battery before doing this to the wires or does it not matter?

No need to disconnect the battery cable. The green wire has no power on it until the horn is activated by the horn buttons or the factory alarm is tripped.

 

[Jessica19699]

ok thanks I will let you know how it turns out

 

[Jessica19699]

ecss, just wanted to let you know I did what you said and the horns work awesome, they must have been bad, but they work great now thanks again for your help, take care