Check all connections. There was also a problem some time back with some of the regulators (or whatever that is enclosed in the box in the wiring harness, that goes behind the passenger seat). Seems like there was a TSB or something on it but I would not swear to that. I don't have access to my TSB list at the moment or I would check for you.

MMZ_Timelord could probably help you better than anyone.....send him a PM.