Chrysler Repair/2003 Chrysler T&C intermittent accessory problem
I have a 2003 T&C, with a 3.3L FFV motor. The problem I am having is INTERMITTENTLY AFTER I start my van, my radio, wipers, heater blower, and wipers will not work. After the van warms up, they will work....could be 5 minutes...could be an hour. If they key is in the accessory position, or run position(van not started yet), they work all the time. After looking at the diagram in my chiltons book, it said the ground control for the accesory relay comes from the FRONT CONTROL MODULE. I replaced that...no change. I replaced the accesory relay....no change. I replace the Integrated power Module(fuse block)....still no change. I cleaned a couple of ground connections going to the frame...no change. I rigged up a relay to give a ground to the coil of the accesory relay, from a spare ignition switched wire coming off the ignition switch, and that made the radio work, but the wipers still didnt. Any ideas? ever heard of this type of problem?
The accessory relay is involved with the radio, power window, widow washer pumps, power outlets, and some other minor items but not the wipers nor the blower. I am not sure why the radio alone would need that grounding by-pass you did if the other items were not similarly impacted as is the radio. The accessory relay is activated by logic of some sort in the power distribution center proper, probably the 'run' position of the ignition switch which in turn is mediated by the body control module. The ignition switch has a large number of internal resistors and the position of the switch is inferred by the body control module based upon what voltages come from the various resistors in the switch. So it could even be an issue with the ignition switch!
The power to the accessory relay and wiper relay appear to both come from the same point inside the power distribution center, and so too the blower relay. When both/all are non-functional, I would be inclined to check if the 12v supply to the rear-most pin at each of the three relays is 'hot' as it should be with the key in the run position. I looked for a common ground fault but I don't find a single point that is shared by all three items. I assume you have checked fuse 4 for the wipers. So I lean toward a common failure of the 12v supply to the 3 relays that is intermittent, but why?
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