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78' Coupe Deville electrical issues

1K views 7 replies 4 participants last post by  77CDV 
#1 ·
Hey guys, first post here hopefully I'm in the right spot.
Having some electrical issues with the power seats, completely dead on both sides, nothing at all. (fuse?)
also the power locks, drivers side dead, passenger side relay clicks, but no action.
Any help would be appreciated! :worship:
 
#2 ·
Power to the windows Ok? There are several connectors in the circuit. I suggest you get out your circuit test light. For the power lock, remove the control unit from the armrest. You can check for battery current and the switch here. You can do the same for the power seats at the same time you check the door locks. If there is current to and from at this point, you should check the circuit for ground. I believe the ground is located inside the cab on the door support on both sides. If this does not get results, you will have to remove the door panel and check for current at the plunger. There is a connector in front of the door, located behind the kick panel. If there is no current to the control switches, you can backtrack to this point and check here.
 
#3 ·
The power seat power goes thru a circuit breaker in the fuse box. A circuit breaker will trip out if the seat motor binds up. Then trip back on once the seat switch is released. All these wires pass thru the door to the body below the door hinge. My gut feeling is there are broken wires inside the rubber cover at the door hinge area. That would explain seats and door locks both being affected.
 
#4 ·
So I might have a slightly bigger problem here. it looks like one of the previous owners was messing with the wires in there. Fuses spliced into wires, connectors not connected, wires soldered together, I might have to call up the previous owner and find out what is up. Electronics Wire Technology Electronic device Electrical wiring
 
#6 ·
It looks like he was trying to bypass the blower motor relay. What a rat's nest! If you haven't already got one, get a factory service manual for your car. It will make problem diagnosis much easier. Good luck with your car! Electrical problems are a real bitch to track down.
 
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