New to Forum, and need assistance on Horn???

[Ninjaman]

Hi everyone, I am new to the forum and would like to introduce myself and say that I look forward to hopefully contributing something that helps someone out down the road, but as of now I am a grand prix newbie and don't have any experience with the cars at all. I bought a used '04 GT for my wife and the car had a few small issues. I have corrected the blower motor issue (new HVAC, seat heater, Rear Def control unit), and the popping sound in the front (loose bolts). But the one thing that I thought would be the easiest has me baffled. The horn will not blow. The fuse is good, pulled the horns and they work if you hook 12 volts to them. I swapped the fuel pump relay with the horn relay, no change. I do not hear the relay clicking at all, so I think that the relay is not being energized. I thought ok, so maybe the switch in the steering wheel is bad??? Then I hit the button on the key fob that should have had the thing honking like mad,....still nothing. So I do a search on here and find a schematic:http://www.grandprixforums.net/f81/w....htmlSomething is funky here because if the horn switch was bad the other horn control relay should cause the horn relay to energize. Any ideas??? I don't really want to tear in the the distribution box under the hood, but I find it hard to believe that the horn switch AND the other relay are bad. But the relay under the hood is good because I have swapped it with the fuel pump relay with no adverse effects, the car still runs, but the horn still doesn't make a sound. No voltage at the plug for the horn at all???I don't know exactly how deep I am going to have to tear into things to get this fixed, but with all the deer and other critters that like to run out in front of us around here, ya need your horn!!!

[Pittman06]

if you check your relay and put power through the terminal to power the horn will it work? Also if you hit the horn switch to you have signal coming to your relay...that will tell you which side you need to check into basically. Btw welcome to the forum!

[Ninjaman]

Pulled the relay and made a small jumper wire to run from positive post of the battery to the female terminal that fires the horn. The horn works everytime you touch the wire to the positive post. So this tells me all the wiring from the fuse box to the horns is ok. I am still confused as to why the relay is not energizing. By the BCM, or the horn switch, something fishy is going on.I even pulled the dash apart to look for any loose connectors, or anything that looked out of the ordinary. No luck.........

[VejGTP]

You could buy one of those little squeeze horns like clowns use and tape it on the outside of your driver door.

[Pittman06]

well then either your horn switch has to be shot or your clockspring is worn. But like i said i would trace your wires from the clockspring forward and see if your getting signal from the switch before your pulling your air bag and wheel looking for issues

[Ninjaman]

well then either your horn switch has to be shot or your clockspring is worn. But like i said i would trace your wires from the clockspring forward and see if your getting signal from the switch before your pulling your air bag and wheel looking for issues

I am still thinking that if I hit the "panic" button on the key fob it should fire the horn. That takes the horn switch out of the circuit completely. I just find it odd that both things that could fire the horn are bad. Today I am going to take voltage checks at the relay to make sure all is well there. It should be because the fuse is good, but you never know what kind of bugs you'll run into with electrical issues. 2 terminals should have 12vdc, the one that feeds the relay, and the one that feeds the contacts for the horn.

[Pittman06]

ohhh, when i read it the first time i thought you said it would work with the remote...well then hell, i have no idea lol, just keep following the circuits and good luck man

[Ninjaman]

Well I figured it out, and got the horn working. It is a problem in the power distribution box. The two terminals on the horn relay that are supposed to have a constant 12vdc had nothing. Once I determined that I hooked my meter inline between the ground and the switch leg and had my press the horn button. It was fine, same with the panic button on the fob. The relay in the BCM was working because resistance would drop out everytime the lights would fire, and normally the horn would be blowing simultaneously. So I knew all I was dealing with was the 12vdc supplying the relay, and relay contacts. I started to pull the distribution box apart and see why it was reading an open circuit between the load side of the 15 amp fuse, and the two terminals on the relay. But I figured that I may open up another can of worms and knew I could shadetree this to work and still have fuse protection. So that is what I did, soldered a wire on the spade of the load side of the 15A fuse, and a wire on the two terminals on the relay. Viola, works like a top with either the horn button or key fob. The wife thinks I was crazy for letting it bother me that it didn't work, but it was more of a safety issue than anything. Now she is telling me how smart I am for fixing it. LOL Now I gotta look into programming the key fob that just came in the mail today. Anyone know the drill on this?

[cerick08GP]

I’m getting my fobs programmed tomorrow. Unfortunately all the 04+GPs seem to require a dealership to do the programming. I even went to my trusty locksmith and he wouldn’t touch it. Although supposedly some can and will do it, just none around here. I’ll report back with the damages, and maybe try to squeeze the dealership for a little clarifying info.



Well, I confirmed my info. The 04+ need to be programmed at a dealership. It will cost you and hour of labor, in my case $45.