Horn does not stop blowing

[Bok97TJ]

Hello all. I've search the forum for my particular horn issue but didn't find it.

Issue: Horn is constantly on when everything is hooked up.

When: I had the TJ outside (Garaged now) with a tarp over it. The Roof is okay with minor leaks at the threaded seams so I wanted to make sure it was dry. We had a lot of rain back to back. One afternoon it started going off. That was a couple years ago. I thought maybe something to do with the moisture.

What's been done: The clockspring was replaced about a year prior to this because the Air Bag light was on. I replaced the clockspring and the light went off the horn worked. I replaced the horns with new ones. They sounded good, no issues.

Testing: I've taken the clockspring out and tested the continuity through it, which was good. I've swapped relays and nothing changed. I tested the horn switch in front of the air bag. There is continuity when the switch is pressed. I even took the air bag out to look at the switch. Nothing looked out of place. I really thought that was the issue. When I touch the horn wire before the clockspring to ground, it beeps. I touched the horn wire after the clockspring, it beeps.

When I attach the clockspring horn wire to the horn switch wire and ground the air bag case, it beeps.

I hooked up a push button in place of the horn switch. When I press the switch and close the circuit, it beeps. I press it again to open the circuit, it stops. Isn't that what the horn switch does? Just closes the circuit when pressed?

Side note: The windshield washer no longer works. I didn't notice that before. Not sure if that is related. I've read others mention the same.

Any help is appreciated. If I overlooked a thread with the solution or guidance, I apologize. Please point me to it. Thanks!

 

[Jerry Bransford]

The horn is energized by the horn button providing a ground connection to the Horn Relay seen below. I highlighted that ground connection in yellow in the below page from the Mopar Factory Service Manual.

If you're not an electrical troubleshooter I would disconnect the battery and use a multimeter set to its continuity checker or Ohmmeter setting (set to Rx1) to see where you first see that ground connection being made. Normally that ground connection should not be see unless the horn button is being pushed.

 

[Bok97TJ]

I will hook the horn up with the battery disconnected and check the ground connection. Thanks Jerry!

 

[Vaquerowrench]

I will hook the horn up with the battery disconnected and check the ground

Did you end up with a solution?

 

[mayorj1227]

The horn is energized by the horn button providing a ground connection to the Horn Relay seen below. I highlighted that ground connection in yellow in the below page from the Mopar Factory Service Manual.

If you're not an electrical troubleshooter I would disconnect the battery and use a multimeter set to its continuity checker or Ohmmeter setting (set to Rx1) to see where you first see that ground connection being made. Normally that ground connection should not be see unless the horn button is being pushed.

View attachment 174720

Have same problem, new clock spring, relay good, horn button checks good . Still have 12v at the plug to the horn

 

[Chris]

Have same problem, new clock spring, relay good, horn button checks good . Still have 12v at the plug to the horn

Ensure that the horn itself has a good ground. If there’s a bad ground connection at the horn, it could be causing it to stay activated. Check the ground wire and connector for any corrosion or loose connections.

Trace the wiring from the horn button to the relay and to the horn. Look for any frayed spots, breaks, or areas where the insulation may be worn off, which could lead to false connections.

Sometimes, even if the relay appears to be good, it might not be functioning correctly. If you have access to another relay, try swapping it out again just to rule that out.

When checking continuity with a multimeter, make sure there’s no resistance when the horn switch is not pressed. This will help confirm that nothing is unintentionally completing the circuit.

If you’ve thoroughly checked these areas and still have no luck, you might consider tracing the system back to where the horn button and horn relay connect to the main harness. There may be a pinched wire or issue further up the line.