Why does the horn on my 2003 jeep went off for no reason?

double posted. wow.
when it beeped, did you look in the display (RPM)
it tells you why?? the VFD or EVIC tells you why.? (rpm dial)
do you park with the alarm on , on the street or a garage?????
if in a garage park and turn alarm off. it does turn off the alarm.
did you bump the panic button?
eg its under your pillow?? LOL or the cat chewed it?
read your other post, it's got lots of answer there.
to find cause.
if the horns stays off, if alarm is off then its not the horn button.

as many will say. there are 4 things that run the horn.
button horn
alarm
door locks.
panic.(part of alarm but not totally)
on my car, i have most themn turned off, like the lamp flashings.
and the horn chirp is off on all my cars, all i get is the door lock click sounds, nice (neighbor friendly)
so turn all all that and see if the horn still fails.

that panic button can fail,
if mind did id pull the fob battery and then use FOB 2.
to see of the FOB fails.

your other post said driving
this one says, parked. 3am clue.

The horn should be behind the grille or on one of the fenders in the engine compartment. If you unplug it and the fuse does not blow I would say the horn is done.

If the battery is good then you have a defective door ajar switch, have the dealer keep the car until it can be confirmed that the horn is going off and it is the alarm system, they can scan it and see what the cause is.

To Larry Crowley,
Did you ever correct the problem to your 2000 Jeep Grand Cherokee and did you in fact determine that the problem was in fact the Body Control Module (BCM)?
I too have a 2000 Jeep Grand Cherokee Ltd with 162,000 miles. Up until just a few months ago, I never had any major problems with the car however in early December one evening the car was turned off and parked in my garage and the horn just went off out of nowhere, a solid horn...it was deafening! We unplugged the battery for the night so it wouldn't drain the battery. The next day I took the car to the mechanic who replaced the horn switch and relay. We thought that had fixed the problem. An hour after I left the mechanic with the car both the BRAKE and ABS lights on my dash went on and my speedometer stopped working (very scary to drive that way). When I stopped the car and went to lock it with my keyfob, the solid horn went off again so obviously the problem was not the horn switch and relay!?!? Over the past few months I have had my car to three different mechanics as well as the Jeep dealer and they have all concluded that the problem must be the BCM but they said that the only was they can properly diagnose the car is if it is acting up with the above mentioned symptoms while in the shop. Unfortunately it only acts up intermitently, not all the time. I am at such a loss. Currently we have removed the fuse for the horn so I am driving with no horn which is extremely unsafe! I look forward to any advice you have in this regard. Thank you!

Check the fuses,and then look at the fusible links,most likely on the starter,if they are good,replace the ignition switch.

you either have 2 horns (a hi note and a low note) and one is defective or you have one horn that is going bad. check possible bad ground also

Hi RS,

The horn on my 86 Cherokee is inside the grill, in front of and to the right of the radiator. I don't imagine they've moved them too far from there in four years.

If you're trying to locate it for reasons other than it not working, I'd say have someone sound the horn while you stand in front of the car. That should pin point it.

Best regards

Mike

Replace horn relay under driver's side dash

You have to look up under the passenger side front bumper.

yes horn relay