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Help Troubleshooting an Unusual Power Window Problem
I know power window threads have been done to death, but I've been pouring through them and can't seem to make sense of this problem I'm having.
Ever since I've owned my 944 the passenger window regulator has been jammed up, it would hum but not move. I pulled it out and cleaned it once which helped for a couple weeks until it slowed back down and froze up.
Recently I decided to put in a good used one, which worked great for a couple weeks, then after sitting for another week it went totally dead. When I opened the passenger door, the drains were clogged and I could hear it was full of water from a recent rainstorm. I assumed it had gotten enough water in there to fry my new regulator, but when I pulled off the door panel for diagnostics that was not the case.
1. I jumped the regulator with 12V, and it still works great
2. I took apart the passenger switch to clean the contacters - didn't help
3. I tested all the switches on the driver's side window, confirming that all the switches work fine.
4. Voltage tests on the switch sockets seemed reasonable Pin 1: 0V, pin 2: 0V, pin 4: 9.9V, pin 5: 11.8V
Here's where it gets confusing. I measured the voltage between the pins at the motor connector, pulling them out of the housing to make sure they were clean and reading correctly, and they fluctuated positive and negative voltage when I flipped the switch, as they should, but at extremely low voltage. changing from about 0.02V to 0.04V when pressing the switch.
I unclipped the wiring harness to check for anything that might have been affected by water, and found these: the unused 4-pin connector which I've read is related to the 10-speaker option, and what looks like some kind of ground splice with that boot connector. Figured the boot connector might be corroded, but I opened it up and it looked brand new, no corrosion. unused 4-pin in door ground splice for power locks?
Finally, I pulled back the accordion boot to see if any wires were broken, and there was some chaffing on the gaff tape wrap, but no obvious problems with the wires. Basically, the switches work, the regulator works, and everything is continuous to alternate voltage to the motor when it's supposed to, but there is extremely low voltage. This seems like it was caused by water exposure, but that could also be a coincidence.
I should mention I also have intermittently working central locks, which may be related, or be worth taking a look at with the door panel off.
9.8V is not reasonable, and 11.8V is not reasonable unless your battery is at 11.8V. Check the driver's side for additional bad connections.
Will do, I figured that could be from a less than ideal ground somewhere, but do you think it's related to the almost complete voltage drop between the switch and motor?