Water-logged & possessed...

With the coming of Spring, I've popped the hardtop off my 90 500SL, and cleaned up the softop.....I actually have better water tightness at the "A" pillars, and experience no leakage at the seal of the windows and top at the A pillar (a problem I DID experience with the hardtop in place!) Now a new problem: after driving at highway speed in rain for about two hours, I got off the turnpike and immediately experienced a new "gremlin", at stop and go speeds. The passenger seat back began assuming an upright position, and when readjusted by the control on the passenger door, immediately continued to "self-adjust" to a full upright and forward seat position.......upon investigation, the rear foot well behind the passenger seat had visible standing water. Once sponged out, things appeared normal, although I did find one wire with plastic connector beneath the rear edge of the passenger seat which was connected to nothing. I assumed it may have gotten water into it, shorting the circuit and activating the seat adjuster motors......Next morning, again drove for an hour, in very light mist/rain.....and at journeys end, had same symptom.....self adjusting seat.....but now the controls have no effect other than a "clickling" of solenoid sound in the seat....they won't move......Please help.....