This weird phenomenon happened twice so far. What happened was when I started the 2003 Jeep Grand Cherokee Limited and several lights came on the dash: ABS, air bag, and Brake, speedometer did not work, no power to the A/C, no head lights, no turn signal, and no wipers. I drove for several miles and the gas mileage just dropped like crazy. I stopped and restarted the car and everything as ok. After driving for awhile, I hit a pothole and the dash acted up crazy again.
i think there is a loose connection somewhere but can you tell me where it is? Thanks

mkvapil;

I've had similar issues on 2 different vehicles; First thing I might check is the battery connections; both the positive and negative; I have seen where a dirty negative connection and/or cables that are corroded will cause a lot of havoc with the electrical system and it will drive you completely nuts!!:banghead:

Good Luck!!