So I have had my 2000 Excursion for a while now and I seem to keep having this problem with the security system when it rains (sometimes). What will happen is I shut it off, walk away, and lock the doors. That's when Matilda starts having fun. the locks constantly cycle, the dome light stays on, and the security light starts flashing rapidly. If I catch all this BEFORE my batteries go dead I can still get everything to stop just by starting the vehicle, but as soon as I shut it off it comes right back. I either have to disconnect the batteries or it will go dead in a few hours. Any help, wisdom, experience, or prayers are welcome.