Horn Blows in Cold

I have a 2001 Dodge Grand Caravan. Once the Mercury dips below 20F the horn takes on a life of its own, often going off for 30seconds at 4:00AM and again on my drive into work. When driving, it is not a constant blast, but a random beeping - as if I had just won the lottery. I’ve had several mechanics look at this, to the point of removing the horn pad and air bag assembly. Lately we have wrapped the steering wheel in a blanket at night which seems to work. I’m considering knitting a horn cozy for use when driving.

Not popular with the neighbors.

Although this has never happened to me, I’ve heard of it happening to other people, usually because the cold shrinks the horn pad and causes it to press against the horn switch.

You could temporarily disconnect the horn wire from the horn during cold weather and reconnect it again in the spring, but then you wouldn’t have use of the horn, which could be (a) unsafe and (b) probably illegal.

Most horn circuits make a ground connection through the switch to activate the horn so the connection is most likely grounding inside the column. Until you can get this fixed you should be able to disable the circuit, for the neighbors at least. I’m not sure if there is a relay in the horn circuit but if there is one you could easily disable the horn by pulling the relay out of the socket. If there isn’t a relay in the circuit then the next best thing may be to pull the fuse for the circuit.

I had the same problem with a 1971 Ford Maverick and my brother had the same problem with a 1977 Cadillac. The problem was the horn switch. If the center of your steering wheel includes an air bag, you may want to disconnect the wires going to the horn switch and install an auxilliary horn button on the side of the steering column. These are available at auto parts stores. It won’t look original, but your car is 10 years old so this may be an inexpensive solution.

The late comedian, Jack Benny, must have had this problem with his Maxwell. He made an entire movie called “The Horn Blows at Midnight”.