Power window problem
Thread Starter
Pro
Joined: Jul 2011
Posts: 508
Likes: 36
From: Ia
Power window problem
The driver side window on my 77 is behaving oddly. When I got the car it worked fine, and then lately the window would only go up and down when the door was closed and now it only works intermittently (still only with the door closed). I'm getting approx. 12v on both wires at the switch (I also swapped switches to eliminate that possibility) but nothing at the motor end. According to the wiring diagram the ground is at the relay, and the passenger side works well so I don't think that's the problem. The only conclusion I have left is that BOTH wires are broken/weakened in the door jam.
Am I over looking something? Has anyone else had this problem? What is the best way to get that wiring harness out of the door to repair it?
Am I over looking something? Has anyone else had this problem? What is the best way to get that wiring harness out of the door to repair it?
Le Mans Master
Joined: May 2003
Posts: 8,874
Likes: 3,551
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
The driver side window on my 77 is behaving oddly. When I got the car it worked fine, and then lately the window would only go up and down when the door was closed and now it only works intermittently (still only with the door closed). I'm getting approx. 12v on both wires at the switch (I also swapped switches to eliminate that possibility) but nothing at the motor end. According to the wiring diagram the ground is at the relay, and the passenger side works well so I don't think that's the problem. The only conclusion I have left is that BOTH wires are broken/weakened in the door jam.
Am I over looking something? Has anyone else had this problem? What is the best way to get that wiring harness out of the door to repair it?
Am I over looking something? Has anyone else had this problem? What is the best way to get that wiring harness out of the door to repair it?
Can simply run a wire from the door- clean metal spot- and touch the battery ground- then see if it works.
Richard
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
Part of your problem, may be two-fold. You might be seeing early symptoms of a dying power window motor and the related problem of that same motor, fighting decades old, grease, that now has the consistency of hardened clay.
Regardless, of the electrical, if you'vd never been inside the drivers door, that time has arrived. It's a common problem with these C3's, that the passengers side is working fine and the drivers side is malfunctioning, as that side gets a lot more use. Fresh white lithium grease, will do wonders.
Regardless, of the electrical, if you'vd never been inside the drivers door, that time has arrived. It's a common problem with these C3's, that the passengers side is working fine and the drivers side is malfunctioning, as that side gets a lot more use. Fresh white lithium grease, will do wonders.
Thread Starter
Pro
Joined: Jul 2011
Posts: 508
Likes: 36
From: Ia
Thanks for the reply guys... I do have the door panel off, in fact I also have the entire center counsel disassembled as well, to track this problem down.
I also considered the driver side window motor to be the problem. So I pulled the plug to it and tested my voltage there, from the plug. On the switch side, like I said I get approx 12v with my voltmeter grounded to the chassis, and I get nothing (well almost nothing) on the plug side with the same ground point. In my mind it leads back to the wires in the door jam.... but I could be wrong.
I would like to be wrong, because I'm not sure how to get them pulled out let alone how I'm going to chase those wires back thru the rubber grommet/sleeve in the door jam
I also considered the driver side window motor to be the problem. So I pulled the plug to it and tested my voltage there, from the plug. On the switch side, like I said I get approx 12v with my voltmeter grounded to the chassis, and I get nothing (well almost nothing) on the plug side with the same ground point. In my mind it leads back to the wires in the door jam.... but I could be wrong.
I would like to be wrong, because I'm not sure how to get them pulled out let alone how I'm going to chase those wires back thru the rubber grommet/sleeve in the door jam
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
Your voltmeter, hopefully, is a multimeter and can check continuity and resistance. Radio Shack sells a pack of test leads, or wires, that have alligator clips on both ends and you can clip one end to a convenient ground to check for a ggod ground and also test for excessive resistance in each wire itself
Set the ohm meter (it's a horseshoe shaped emblem) to thd lowest number, usually 20 ohms. You shouldn't see more than five or six ohms in any circumstance, nor should it infinite or open.
Set the ohm meter (it's a horseshoe shaped emblem) to thd lowest number, usually 20 ohms. You shouldn't see more than five or six ohms in any circumstance, nor should it infinite or open.
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
Also, most test leads on just about any good test meter, has needle points so you can stab the wire you're testing, through the insulation to get a reading. You can unplug the wire in the back, if I'm not mistaken, it takes some hand yoga, that's for sure. Most auto parts stores sell the CFC Electronic Cleaner and this, combined with sanding the corrosion of the contacts and using a metal nail file to clean the female part of the connector may help too. You'd be surprised at how corroded the connectors get after decades. Good Luck and keep asking questions, if you need to.
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
Wiring maybe broken or neatly into where the harness bends back and forth , when the door is in a certain position the wire bends and makes an intermittent contact inside the plastic insulation ....you can t see any problems. But one of the wires may have a break in it.
You might be able to have someone hold the window button in the on position . While with the door open move the harness in the area that flex would occur and see if you can induce a intermittent operation of the window.
You might be able to have someone hold the window button in the on position . While with the door open move the harness in the area that flex would occur and see if you can induce a intermittent operation of the window.
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Thread Starter
Pro
Joined: Jul 2011
Posts: 508
Likes: 36
From: Ia
I think I found my problem!
after checking for continuity, and deciding at least one of the wires was bad. I pulled the grommet and harness out of the door, unwrapped the tape and this end came off in my hands...
Good news is that it wasn't as bad as I had feared to get things out of the door. Now to get things fixed and maybe run some new wire for LED courtesy lights under the doors
after checking for continuity, and deciding at least one of the wires was bad. I pulled the grommet and harness out of the door, unwrapped the tape and this end came off in my hands...
Good news is that it wasn't as bad as I had feared to get things out of the door. Now to get things fixed and maybe run some new wire for LED courtesy lights under the doors