Electrical Horn keeps blowing fuse and radio not working

sav22rem22

Active Member
Feb 6, 2020
192
23
28
19
North Carolina
Hello all. I'm back again with more issues of course. A few weeks ago I was dumping codes and my cats started to walk towards the car so I went to blow the horn and instead of the horn blowing I heard a click and then nothing. Fast forward to a few days ago I finally got around to buying the 20A fuse for the horn and I put the new one in and hit the horn button and once again pop. So today i did some searching and found that some people fixed this issue by unplugging power to the cigarette lighter so I did just that. Now my fuse pops as soon as it touches the terminals. What should I check now? Also the other night my radio was working just fine. Its a kenwood bluetooth radio nothing special and its not connected to any subs just the door speakers and the speakers in the back. Then the next morning the radio just didn't turn on although it was working the night before. I checked the fuse on the fuse panel for the radio and its fine but still no radio. Any ideas? once again thanks for any help
 
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jrichker

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Do the horn first...

Simple first step. The horn shares the same fuse as the cigarette lighter. Look closely at the lighter socket and be sure there isn't a coin or washer laying in it.

The horn circuit has a button that supplies ground, a relay that uses the button to switch the horns on and off, and two horns. The relay reduces the current that the horn button has to carry. This makes it possible to use a small and simple switch and slip ring on the steering wheel.

Note that the horn ground is built into the horn mount bracket, so the horn must be mounted on metal with a good connection to the car body.

attachments\50337





The horns typically develop an internal short to ground, which causes the fuses to blow. :eek:

The horns are located under the car on the driver's side, forward of the front wheel well. Disconnect BOTH horns, replace the fuse: if the fuse blows immediately, the problem is most likely in the cigar lighter circuit. If not, then press the horn button on the steering wheel: if the fuse blows the problem is in the wiring between the horn relay and the horn. If doesn't blow when you press the horn button, connect ONE of the horns and try again. If it still doesn't blow the fuse, connect the other horn. Chances are that the first horn you re-connect will blow the fuse. Whatever horn blows the fuse at this point has an internal short and is trash. Time for a trip to the junkyard... :crazy:

Horn does not honk, but does not blow fuses:
Run a jumper wire from the battery positive terminal to the horn input connector: the horn should honk. If it does, then your problems are in the other parts of the circuit. If it does not honk, replace the horn.
Use a test light or voltmeter and connect one lead to the horn wire under the fender and the other to ground. Push the horn button: you should see 12 volts or the test light will turn on. If it does not, check the fuse. If the fuse is good, check the relay.

The relay will click and honk the horn if you short the Yellow/Lt Green wire to ground. If you have a test light connected in place of the horn it will light. If it does not activate the horn or test light, look for 12 volts at the Lt blue/white wire. No 12 volts at the Lt blue/white wire, you have fuse or wiring problems in the circuit that supplies the 12 volts to the relay. Good 12 volts at the Lt blue/white wire and the Yellow/Lt Green wire shorted to ground and no honk or flash of the test light, replace the relay.

The rubber foam usually deteriorates over time and that is what makes the horn switch fail. Take it apart and replace the foam with some from packaging material. A little creative engineering may be required, but you can do it.
 
Last edited:

sav22rem22

Active Member
Feb 6, 2020
192
23
28
19
North Carolina
Do the horn first...

Simple first step. The horn shares the same fuse as the cigarette lighter. Look closely at the lighter socket and be sure there isn't a coin or washer laying in it.

The horn circuit has a button that supplies ground, a relay that uses the button to switch the horns on and off, and two horns. The relay reduces the current that the horn button has to carry. This makes it possible to use a small and simple switch and slip ring on the steering wheel.

Note that the horn ground is built into the horn mount bracket, so the horn must be mounted on metal with a good connection to the car body.

attachments\50337





The horns typically develop an internal short to ground, which causes the fuses to blow. :eek:

The horns are located under the car on the driver's side, forward of the front wheel well. Disconnect BOTH horns, replace the fuse: if the fuse blows immediately, the problem is most likely in the cigar lighter circuit. If not, then press the horn button on the steering wheel: if the fuse blows the problem is in the wiring between the horn relay and the horn. If doesn't blow when you press the horn button, connect ONE of the horns and try again. If it still doesn't blow the fuse, connect the other horn. Chances are that the first horn you re-connect will blow the fuse. Whatever horn blows the fuse at this point has an internal short and is trash. Time for a trip to the junkyard... :crazy:

Horn does not honk, but does not blow fuses:
Run a jumper wire from the battery positive terminal to the horn input connector: the horn should honk. If it does, then your problems are in the other parts of the circuit. If it does not honk, replace the horn.
Use a test light or voltmeter and connect one lead to the horn wire under the fender and the other to ground. Push the horn button: you should see 12 volts or the test light will turn on. If it does not, check the fuse. If the fuse is good, check the relay.

The relay will click and honk the horn if you short the Yellow/Lt Green wire to ground. If you have a test light connected in place of the horn it will light. If it does not activate the horn or test light, look for 12 volts at the Lt blue/white wire. No 12 volts at the Lt blue/white wire, you have fuse or wiring problems in the circuit that supplies the 12 volts to the relay. Good 12 volts at the Lt blue/white wire and the Yellow/Lt Green wire shorted to ground and no honk or flash of the test light, replace the relay.

The rubber foam usually deteriorates over time and that is what makes the horn switch fail. Take it apart and replace the foam with some from packaging material. A little creative engineering may be required, but you can do it.
Thanks again Jrichker. After some looking around I'm pressure sure I've narrowed it down to my horns being bad themselves although I have had some issues with the foam pad for the horn button. I'm just going to replace the pad and the horns. I've unplugged power to the cigarette lighter and I still get an immediate pop. Will update when that is done.