I have a 96 grand cherokee and every once in a while, the check engine light will light up and then either the volt meter or the gas gauge will drop to zero. It doesn't affect the engine at all. The vehicle still drives fine and if you stop and turn it off and back on everything is normal again. I'm stumped and can't figure it out. Any suggestions?

Run the troubleshoot program codes. Details are on the Grand Tech page here at NAGCA. Hope this finds your problem.

My 93 was doing sort of the same thing, ended up that the ground connection to the battery was bad. The actual wires were coming out of the battery connector at the battery... Not sure if that's it but it's an easy thing to check