security meltdown

[JeffN]

Here's an oddity: driving in a pouring rain, our 1997 stock security system went haywire and the security module started clicking for five minutes until we shut off the ignition and then it was fine. After that, the dash security light went dead.

Next time out in the rain, the horn honked for about 2 seconds while driving.

Went to Metric Sube, they looked at it and found nothing.

Today in the rain, the same thing with the honking for 2 seconds. Any clues aside form moving to the desert?