My drivers side window works sometimes, sometimes it doesn't, if i take the motor out of the door, it will work fine. If it touches the door, there will be a ark of electricity. Sometimes i can bump the door and make it work. Did change out the motor and switch, no different. Hate to pay an auto electrician if i can get away with it.

 

Kind of sounds like a ground problem. Without knowing specifics, I'd trace the wiring that comes into the door, looking for a ground wire that is no longer connected to the door, or has broken right in the place between the door and body where it kinks most. I have heard of wires breaking due to all the bending back and forth of opening and closing the door.
Can you get to the motor wiring when the motor doesn't work? You can see if you have vaoltage there when you press the switch. If so, you have a bad ground.

Chris

 

Check that the wiring in-beween the door and dash isn't damaged.

 

Remember on 12v systems in order for the motor to go both ways the pos. and neg. have to reverse,what was once pos. is now neg, it changes at the switch then one wire to grd.


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94 2500 cummins 4x4 2500 auto got it here 2 wks.ago.