1999 Plymouth Grand Voyager, Horn Will Not Turn Off

This 1999 Plymouth Grand Voyager came in with a complaint that the horn would not turn off. My first thoughts were either a stuck relay or a sticking horn switch. I tried the horn and it did not work at all. I located the horn relay and found that it had been removed by another shop.

I installed the relay into it’s correct position. In the following picture it is shown installed on the lower row to the far left. I tried the horn and sure enough it would not turn off. I disconnected the relay and headed under the dash.

I removed the steering column covers by removing the phillips headed screws. I then located the connector at the steering column clock spring assembly or air bag contactor as some call it.

I disconnected the harness that had the horn switch wiring in it. Notice the yellow connector to the left. That is for the air bag. Leave it alone. I put the relay back in to check the system and found that the horn was still stuck. Oh no there must be short in the wiring. I did some quick checking and saw nothing out of place or damaged. Time to look at a wiring diagram. Even worse the Body Control Module (BCM) is located in between the switch and the relay. maybe the relay is just stuck. Please be something simple is all I could think.

Thank goodness it was a simple problem after all. I still do not quite believe it but it was poor battery positive terminal connection. You can see the light colored arc mark on the inside of the terminal just below my thumb.

You can also see the corresponding arc mark on the positive battery post. I found this one by luck I guess. I was testing the relay at the battery negative terminal and needed to hook my test light to the positive terminal to perform a test and accidently found the corroded and loose cable connection. I cleaned the terminals, tightened the cable connection and the problem was fixed!!!!!