I'm honkless! Please tell me if my deduction (aka guess) is right

electrical-wiring
pontiac
#1

*Disclaimer: I am by no means a mechanic (nor did I sleep at a Holiday Inn Express last night). I love cars, and I can change my own oil and tires and a few other basics, but the following is just my brain trying to be a little more mechanical. (end disclaimer).



I have an 05 Grand Am. Bought it used, hate it. And I’m a Pontiac girl, so that’s a hard to confession to make.



Anyhow, a couple weeks after I bought it, the horn started being dodgy. It would take a few pounds on the wheel before it would honk. Once it did honk, it would work for a while unless I didn’t honk for a while, then it would stop again. The number of whomps before honk increased as time went on.



Took it back to the dealer (“certified vehicle”) and they fixed it. And it stayed fixed for a while. My receipt said, “Fixed horn”. Then it started doing the same thing again after a couple months. Now it won’t honk at all.



The interesting thing is, it also won’t honk when I use the key fob to lock the car (it did work when I bought the car and after the repair). Nor will it honk when I use the delay lock by pressing the lock on the door before I close it.



I called the dealer (off warantee now) to find out what they did to fix it the first time and THEY WON’T TELL ME. So I called a few local shops and they all say it’s probably in the steering column and they don’t do that stuff. GR.



But to me, since it won’t work from the fob either, -I- think it must be the horn itself, or maybe wiring to it. I don’t know where the receiver for the fob is located, but I’m guessing it isn’t in the steering column and is somewhere between there and the horn?



So, please, tell me what you think - set me straight on this. And while you’re at it, what do you think I should plan to shell out to get this fixed?

#2

Oh! One more thing I just thought of. Prior to this, my car had already quit honking altoghether. The other evening - a VERY cold night (snowed that day, ice everywhere), I was parked at a restaurant for dinner. After dinner, I started the car and put it in reverse to back out of my spot. After rolling a few feet, I heard a blaring horn. Took me a minute to realize I wasn’t about to hit someone, it was my car. Constant on kind of honk, for about two minutes. I put the car in park, turned of the car, beat on the horn, pushed all the buttons on my key fob, nothing worked. Then, as I was getting ready to get out and call someone, it stopped. Hasn’t honked since.

One more thing: it appears the car was in a wreck before I got it. This was NOT on CarFax but I had asked a mechanic to balance my headlights when I went in for my first service cause the right one shone well above where it should. He said the can had been damaged in a wreck (that was the first I’d heard about that) and he’d straightened it out as much as it could but it needed to be replaced. Isn’t that in the same vicinity as the horn???

#3

I agree with your logical deduction of the horn itself being the trouble or possibly a horn relay if it has one. To see if it is the horn you can run a jumper wire from the battery directly to horn and see if it works. That will verify if it is ok at least. If that is good then the relay is the next best choice. Checking for a loose connection in the wiring to the horn is good to do also.

I see you have more info now. I found some service data on this and it shows fuse 43 in the panel under the hood supplies power to the horn circuit and there is a relay for it also in there. The trouble very well could be due to the previous accident damage. Check to make sure the fuse is ok. The horn switch makes a ground connection to the relay coil to activate the horn and there may be a short in the steering column causing that trouble.

#4

Hi, OP here.

I did switch out both fuses that the manual said had anything to do with the horn - one was under the hood, the other in the door compartment. Neither made any change.

I’m going to sit here and read your last sentence a few more times before I understand it.

My company’s garage is at the site I’m at today, so even though it’s not a company car, maybe I’ll see if they don’t mind running the jumper from horn to battery test for me.

#5

I suspect the horn itslf is ok after reading you updated info. The trouble is most likely within the steering column. The service data also shows a connection to the BCM module so it may have caused the horn to sound also.

#6

Horns are grounded via the mounts to sheetmetal in areas subject to rust. It’s very common for the mounting to become corroded and the ground lost, sometime intermittantly.

Look there first.

#7

Check in this order.

  1. Check Fuse.

  2. Jumper horn to see if it works.

  3. If it doesn’t, use a multimeter or light, and check the circuit before replacing horn.

  4. If the horn works, or a substitute in line 3 is used, check the relay and circuit.

  5. Check the circuit from the horn button to the relay.

#8

Based on the fact the car has been hit, the bags gone off, and the turning of the steering wheel causing the horn to operate I’d say the problem is likely in the steering wheel horn contact, which can be a somewhat fragile item anyway.

No idea on costs as I’m more of a “foreign car” guy and my experience on these is very limited, but one would think not more than a couple or three hours labor.