JThomas

2007 Z06, owned since new in October of 2006.

Washed the car this morning at local coin/spray wash. Sprayed engine compartment, because it was "dusty". Got home and was completing the wash, by doing windows, tires, etc.

While working on interior, I wiped down the steering wheel and blew the horn, no big deal. Now I go to cover the car, and the horn starts blowing. It stops, then starts again to blow and keeps blowing. I check it, and there is nothing "jambed" in the steering wheel that would cause it to continue blowing.

I start the car to make sure it is not in some crazy alarm mode, but the horn continues to start and stop blowing. It was like the car was possessed! While the car is running and the horn is blowing, I open the hood to see if I can disconnect the horns. I locate them but can't disconnect. I then try to get back in the car and I can't open the doors. The keys are in the car, the car is running and I can't open the door from the outside.

My wife grabs her fob for the car to unlock it and gain entry and was able to do so. I shut the car off, and the horn keeps at it. On/off, etc.

I then go for the battery and disconnect. Anyone experience this issue before? If so, what was the solution? If not, any ideas what could be the problem? Both fobs have new batteries in them, since the beginning of the season (March)

JThomas

Well, I let the car sit for over two hours, with the battery disconnected. Reconnected the battery, gained access to the car with my fob, started it and so far no issues.

I hope this isn't the beginning of any gremlins.

tractorguy

I had a similar experience with my 2009. New owner. The first time I washed it I also washed under the hood with just garden hose and cloth rag. No interior work at all. Was in the house and thought someone had driven up to garage sounding their horn. Went out and it was the Z except it was steady not intermittent like you describe. I did everything with the FOB I knew to do. Started it several times but continued blowing. Finaly unhooked the battery cable. I later charged the battery, reconnected and everything fine. Like you wondered if had a gremlin but it has been over a month with no more problem. Cheers FB

JThomas

Thanks for the response. The car just turned 38,000 miles so it's not as if the engine bay was dirty, but lesson learned, maybe I should not spray the bay and electronics. All seems to be well. Now to reset the clock and possibly radio stations and such.

jimbob8915

Been there done that. I pressure washed my engine after my head rebuild. It was like an hour later an horn started blowing an would not shut off. I disconnected the battery, then I disconnected the horn. I reconnected battery an left horn disconnected for two days. I figured water got in somewhere, but was really unsure where it would need to get to give the horn a short.

JThomas

That's what I like about the forums, sometimes it just lets you know that someone else has already been down that road. Thanks for the response.

chpmnsws6

This just happened to me last night. I washed the car after some low life spit on it while I was shopping at the auto parts store I've worked at for 10 years. I just bought the car and the engine bay had some rocks, leaves, and dust I wanted cleaned off. At 2:45am it honked for a few seconds. I told SWMBO that it sounded like it was across the street. A few minutes later all hell broke loose and the only thing I could do was unhook the battery. Because we currently live in a duplex with a semi shared garage with only a thin party wall, I didn't want to disturb the neighbors anymore then I already had. I now need a new battery terminal and possibly a battery. In one week of owning it, the column lock (2005 m6 that I now have an eliminator sitting on my desk for) has left me stuck in the garage, it's been spit on, and its woken up the neighborhood in a possesed manner. Will this slow down or is it a sign!??

gaklid

z06clif

Sounds like water made a connection somewhere . Do you have an air blower of some kind to dry under the hood?

Clif

jimbob8915

I would lve to know where the damn short comes from. I have not washed my engine compartment since it happened

ZIE06Bernie

If you had the key fob in your pocket you may have pressed the red alarm button by mistake. Easy to happen.

jimbob8915

My situation was not a panic alarm horn cycling. It was car horn blasting away and only stopped when I disconnected the battery. I then after calming down disconnected the horn. There must be a relay that can get moisture in it because obviously the horn button in steering wheel was not wet and the plug at horn has no switch in it.

RossN

This happened to me almost exactly as you described, washed the engine bay, drove it for 30 minutes, parked it and 30 minutes later the horn starts going off.

I had disconnected the electrical connector near the horn, front right side of engine bay, reached from the bottom if I recall...

ZIE06Bernie

Sorry I may be misinterpreting the "blowing intermittently" heading of the OP.

The relay is number 34 under the hood. Not common for a relay to operate via water with 12 volts but possible. Take a look at the wiring operating the relay to see if any partial short to earth exists - be careful because the wiring also commons into the BCM.


If you need a circuit just holler.

chpmnsws6

I swapped relays with the same horn blowing result. For the next few days, the revlimiter will have to be my horn. It works as it should now, but I'm scared to leave the relay in for now.