There is a starter relay that is in the power distribution center, but that does not sound like it would be the problem. I really no clue but try finding the wiring diagram for your jeep and tracing the wires back and see if they go to the same area, then do a process of elimination. Wiring diagram I was looking at shows starting and heating control wires going back to the Engine Control Module(ECM) but that was for a '94. I do not know if there is that much of a difference in 1 year though?