Went to start the car in the morning, started up, several seconds later the horn just goes off and won't quit unless I turn the car off!

I thought this could be because I replaced my steering wheel several weeks back (no issues or changes to the car in the meantime) so I thought maybe I somehow tightened the airbag section on too hard, so I loosened it up, but the horn still keeps going!

I pulled the two horn fuses in the engine bay to stop it but obviously that's not a solution.

Is there a possible short that I could check for, or is there a switch or contact in the steering wheel that I should check?

 

Is it definitely the horn and not the Security Sounder?



Graham

 

Thank you for the diagram Graham, but two things make me think it's the horn:
1. because when I pulled the two horn fuses from the engine bay fuse box the honking stopped, and
2. If it were the security system, why does the car still start up fine?

I'm really puzzled and not sure how to go about fixing the issue here - anyone have thoughts on this or has anyone encountered this before?

 

Hi Pomosv,
I've just looked at the diagram for the horns.
There is the switch in the steering wheel that could be stuck or you could try swapping the horn relay in the engine fuse box to see if that is the problem.

From the drawing I think unlikely to be a short.

Hope this helps,

 

Sorry - I misread the effect of pulling the horn fuses.

The horn operation is complicated by control through the BPM (Body Processor Module). The steering wheel pad switch signals the BPM to sound the horn. The BPM horn-output connection responds by providing an earth path for the horn relay coil. The relay contacts are subsequently closed and the horns sound.

Graham

 

JTIS is exceedingly unhelpful re the horn switch.
My bet is (since it is subjected to continuous wear by steering wheel rotation) the wiring harness will be the culprit.
You MUST disconnect the battery earth and wait 5 minutes before messing around in the steering wheel - the air bag deploying would spoil your day.
Then
Detach the driver air bag module.
Rotate the steering wheel 90 degrees counterclockwise to provide access to the driver air bag module left-hand retaining bolt and fully loosen the captive retaining bolt.
Rotate the steering wheel 90 degrees clockwise to provide access to the driver air bag module right-hand retaining bolt and fully loosen the captive retaining bolt.

Treat the removed airbag with respect.
Again from JTIS
CARRY A LIVE AIR BAG MODULE WITH THE AIR BAG AND TRIM COVER POINTED AWAY FROM YOUR BODY. THIS WILL REDUCE THE RISK OF INJURY IN THE EVENT OF AN ACCIDENTAL DEPLOYMENT. FAILURE TO FOLLOW THIS INSTRUCTION MAY RESULT IN PERSONAL INJURY.
DO NOT SET A LIVE AIR BAG MODULE DOWN WITH THE TRIM COVER FACE DOWN. FAILURE TO FOLLOW THIS INSTRUCTION MAY RESULT IN PERSONAL INJURY.

If you haven't already do download JTIS from the HOW-TO section.

 

If all else fails put a "honk if you're horny" bumper sticker on it


P.S. hope that does'nt get me in trouble with the mods.

 

Update: figured out what was causing the honking. One of the wire connections inside the steering wheel (under the airbag) came loose, and in doing so touched the metal frame of the steering wheel (grounded) which completed the circuit and sounded the horn. I tightened the crimp on the connector and put the connection back in its place, and all is good!

 

Thanks for the diagnosis

 

Airbags scare the hell out of me. Only time I removed one was from a Chrysler van. I am always amazed when I see the idiots on TV playing games with them -- putting them under chair cushions for example. Although maybe that will help thin the herd.