I live in MN so it gets cold in the winter. The first real cold day of the 2005 winter I went out and my battery was dead. It was an older battery so I just figured with the weather and all I just needed to replace it. Bought a new battery and the instant we connected it the horn started blowing. The horn did not stop blowing until we figured out what fuse it was and pulled it out. Realized the horn was probably blowing all night to drain the battery (not sure how long that takes, but the neighbors probably didn't like it). Didn't really care so I did not get it fixed right away.

The next spring I replaced the fuse and horn worked fine until the first cold day the next winter and I was sitting in my living room and heard somebody blowing their horn for a long time. I looked out the window and nobody was driving by and realized it was my car again. Some sensor must be screwy and when it gets cold enough it contracts or something weird like that. I took the fuse out again and just have not had a horn for the last 4 years.