The main cluster/ plug behind the dash is famous for that, particularly in '97's. Mine did it off and on for a while, but it turned out to be the main ground ribbon or some related connection that got fixed at the same time, so I never had to open it up and get in there. From what I understand it's a serious PITA. Good Luck.

97tj, Shaved Ford 9 rear, 4:10's, New 35x12.5 BFG KM2's to test!, Warn x8000i, ARB's, Quick Disco's, Hand Throttle, & it's my DD. smile