'99 Century under voltage at window switch

UtahGuy

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My power windows have not been working in this car for sometime. I always just assumed it was the master switch, so I finally got around to buying one.

I installed the new switch but the windows still don't work. After taking a multi-meter to it I discovered the yellow hot wire is only at about 5 volts. When I connect it to the switch it drops to .6 volts.

The dark blue wire that brings line voltage to the other switches also registers at .6 volts so I know the switch is working.

I'm confident that the ground is in good condition because the lumination wire shows 10.5 volts to the ground wire.

What would be causing this under voltage? Thank you in advance.
 
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If you are saying that when you connect it to the switch AND press the switch, the voltage drops to 0.6, then I would suspect a bad connection somewhere that can't support the amp draw from the motor

Or an old and bad wire than can't support the draw
 
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Thanks for the reply Wildcat. No, it drops to .6 without having a button pressed. When I press a button it drops to 0.

When I release the button it climbs back up VERY slowly, taking probably 30 seconds to get back to .6. When I turn the ignition key off it drops very slowly, taking 30 seconds to get back to zero.
 
Hook an amp meter up between the yellow wire and the switch to see it there is a draw. If there is, then there's probably a short somewhere between the driver's switch, and the other doors.

If you Lock the windows using the switch on the driver's panel, does the voltage come back? If it does, then do the windows work? if one doesn't but the others do, then there's a drain in the wiring for than door.
The lock button stops the power being transferred from the driver's switch to the remaining window switches and would stop a short if there is one.
 
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Hook an amp meter up between the yellow wire and the switch to see it there is a draw. If there is, then there's probably a short somewhere between the driver's switch, and the other doors.

You'll have to help me a little bit with this. Between the yellow wire and where on the switch?

If you Lock the windows using the switch on the driver's panel, does the voltage come back? If it does, then do the windows work? if one doesn't but the others do, then there's a drain in the wiring for than door.

The lock switch doesn't change the voltage reading at all.

For good measure I unplugged the harness that has the wire carrying current to the other doors and I still see the voltage drop.

It's still also reading 4.5V from the wire directly to ground. I'm guessing that should be 12V?
 
make sure you have good power at fuse first. if so, I would investigate the harness where it feeds thru the door to the dash. the harness inside that rubber conduit is a problem area after opening and closing the door for 13 years.
 
make sure you have good power at fuse first. if so, I would investigate the harness where it feeds thru the door to the dash. the harness inside that rubber conduit is a problem area after opening and closing the door for 13 years.

Yep, while you were posting that I was stumbling upon the same thing!

Here's what it looks like:

harnesss.jpg


That is the ground and hot terminals that are burned. I pulled it straight and flatted down the female end, which was melted. I snapped it back together and have 14V at the switch now. Motors work!

They aren't actually fitted together, just pushed tight against each other in the harness. I probably shouldn't leave it like that, so what would be the best way to do a permanent repair on that? Can I just bypass the harness and run two wires through the door?

Thanks for the help!
 
Awesome,
You could run two wires that bypass the connector (make sure you don't use a smaller wire than what's already there). But I would go to an electronics store (or some auto parts stores carry them) and get a couple quick disconnects to put in the wire where the other connector is. That way the door can still be removed later without needing to cut the wires.
 
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