Grand Caravan electrical kookiness

Our 2002 Grand Caravan has no wipers, radio, heater fan or window control for the first 5 to 55 min. of driving. When engine is off they function in both AAC and Run positions of the key. When the rear wiper is turned on the radio/clock flashes on while the wiper blade is in motion; off while the blade pauses!?!?! FCM has been replaced and I’m told ignition switch checks out OK. Please help; this is driving me bonkers!!

One possibility would be a bad chassis ground somewhere. One hint is that the rear wiper seems to find a ground through the radio/clock. After the car warms up, apparently the ground then makes contact. A shop that specializes in electrical problems is probably your best bet.

I think Triedaq is correct about the grounding. You could try using a jumper lead to tie a known good ground to the dash area or directly to the ground for those devices to see if that is the case. If that doesn’t work then check to see if those devices tie to a common power point and check for trouble there.