Rodeo works without keys

I just recently bought a 1999 Isuzu Rodeo. I had this car for about 2 weeks and was very pleased with my purchase. Then it snowed. One morning I woke up to about an inch of spring snow/slush on my Rodeo. I went outside to start my car up only to realize that the batterey was dead. I went to Autozone and purchased a new batterey and thought that my problems were over. They weren't. After installing the new batterey I got in my car and was getting ready to start it up. With my keys in hand I placed my foot on the brake and much to my surprise the heater and dome lights kicked on. Mind you that this all happened with the keys in my hand. The door open chyme also began to chyme for about 10 seconds. I took it down to the dealer and they thought the problem was fixed. I went and picked up my vehicle in a very strong down pour of rain. I took my car home and realized I had to go to the grocerey store. Once again with my keys in hand I put my foot on the brake pedal and the heater/ ac fan started up again, the dome lights flickered again, and the door chyme chymed again. Does anyone out there have any idea to what is going on with my vehicle? Thanks

GHOSTS!

Clean up your ground points first, where the batter grounds to the Body and the alt bracket.

Also, there was a recent post here (or maybe on the trooper board), where someone had an electrical problem and the dealer thought it was a short in the dome light (they have to take down the headliner to get to it, I guess).

Do you hear a disembodied voice saying "geeeet ooout!!" Cause if you do, don't be a dummy like in the movies. Just get out. :crying:

sounds like your only have this problem when the vehicle is wet and u depress the brake pedal. so next time it rains and does it, id suggest you pull out the fuse for the brake lights. if there is a relay pull that too and see if itll still do that