Windows Regulator Problem?


I own a 2002 Chevy Silverado 4x4 v8. My window regulator (passenger side)started to work on/off. Sometime it would go up sometime it wouldn’t. I decide to buy a new one. I first tested the plug-in for power and got power on up and down. I bought a new regulator assembly and installed it. I’m getting the same results. Sometimes it works, sometimes it doesn’t(mostly doesn’t work). I’m at a loss at this point. What could be causing this. If it’s a switch problem then the driver switch would still work(doesn’t work either). I tested the switch and power connector with a tester light. Any help or suggestion would be appreciated.

The problem might be in the wires, particularly at the door hinge area where they are subject to flexing every time the door is opened and closed. There could be breaks inside the plastic insulation making them invisible to casual inspection.

it also may indeed be in the drivers side switch. all the other switches operate from the drivers side.

as a further test, at the drivers panel swap the passenger side front window wires with the rear sires. see if the problem follows the switch or the regulator. this may require you to figure out how to get the wires out of the plugs without damaging them. usually a small thin probe inserted in the correct location will press the catch so you can push the wire out and reinsert it into the other connector location.


Cappy’s post got in just ahead of me but his first sentence echoes my answer.

My drivers’ door power window started to act up on me too about two weeks ago and finally stopped closing.

It would open but reverse the switch and no go.

I thought the problem was the window motor too, until I took the panel off and tested the switch and motor for continuity.

Yep, juice going through to each, but the window motor would only crank down.

So, off to a wrecking yard and find another motor.

Hooked it up (tested before buying) and found the same action.

Hah! I figured then the fault was in the switch and sure enough it was.

$50 plus 2 gallons of gas chasing around and it works again.

See if another switch does it.

Like all vehicles that leave these armrest mounted switches exposed to the rain that falls in when the window is down (like when you go to a coffee shop drive through) the switches corrode and although they are ‘sealed’ from the factory, water does get in and makes then lose contact.

BTW, I found when I had the drivers window switch out, the passenger side wouldn’t work. Once the new (used) switch was in, the passenger side worked again. So, in reality, it loses continuity.

Sorry for such a long-winded reply.

You did get a new motor with that regulator didnt you? GM uses a “reversing polarity” technique on its window motors. You nee a test light that shows the presence of either ground or battery voltage whatever is present. If you activate the master switch to send the window up one wire at the motor will go “hot” the other must show ground.Wnen you send the window the otherway the situation reverses. If you dont see this situation its the switch.

If you buy a new driver’s switch console, you will probably have to go to the dealer. I tried to buy one on line for my 1998 Regal, but the two places that sold them were out. It turns out that the price was the same as the dealer, and the dealer could get it faster. Clearly, this is a dealer-only part. For my Buick, anyway. You can look at eBay Motors, too, but I think you’ll have the same success that I did.

I just wanted to thank all of you (AlenY, cappy208, RoadRunner, oldschool, itsanders) for the quick replys and for your suggestions. I tried to take the passenger door switch off and hook it up to the driver side. But the plugs only fit into each individual switch. What I don’t get is, does power from the battery go to the driver side switch or both switches? If it was the driver side switch that was the problem, would I still get a reading of 11.98 volts when pressing the up on the passenger switch and 11.98 volts on down.

Power goes to the drivers door command first because all windows (the exception being the rear quarter windows) can be operated from there.

What I mentioned in my post was that when my drivers switch was out, the passenger side wouldn’t work. SO…I have to assume (hate that word) there was no power going there.

I didn’t go so far as taking the passenger door power window switch out and test it.

I’m wondering about your last statement. Did you test for 12V at the passenger switch with the drivers switch disconnected, or are you simply asking if that would happen?

I guess what I’m trying to say is that my driver side window works fine and when I hit the lift switch for the passenger side window(on the driver side switch) it clicks both ways. Signaling that it is working. The plug from the door wiring to the window regulator motor has tested power both ways. The motor in my new windows regulator is working fine. At this point I can only assume the window is binding with such resistance that the motor is unable to lift it or the power plug to the motor is not contact the polls. I am going to take off the trim and see if something is binding(or sticky inside the trim) and then replace the power plug to the motor.

I have a 2 door 2002 Chevy Silverado. If I remove the driver side switch, I still get power to the passenger side door. Yes I tested for power at the passenger side door and get 11.98 volts both ways.This is my second after market part bought new off ebay. I have the first windows regulator, and test for resistance on the motor and it has zero resistance. I test with 12volt power supply and the motor works fine. I can only assume that my assumption is correct, either the window is binding or the wiring power plug is not contacting the power polls on the motor properly. My hunch is that the window is binding some how. Possible something sticky in the window rubber seals!

Try spraying a clear silicone lubricant into the window channels. While it might not cure a severe bind which could need a mechanical adjustment, it will help free it up enough to test your theory.

hey devin:

i may have not been clear about the wires. i meant switching the wires only at the drivers side switch. in other words, make the drivers window button work the passenger window, or rear passenger work the front. not actually switching the switch themselves.

if you do need a new window switch don’t bother go to a junk yard. usually a junked car will have the door open, or window down, so the switch will probably have rain water damage.

you mention getting 11.98 volts while pushing the switches. where are you getting that from? the other side of the switch, or at the window motor?

if you are getting it from the other side of the switch, but not at the motor, then likely the mentioned door flexing has killed the wires inthe door hinge area.

When the window motor is removed, the window can be slid up and down by hand, although the Haynes manual says to release the glass from the regulator first and raise and lower the glass that way.

Check for binding first and later let us know what you found.

Hey cappy208,
Yes I’m getting the 12 volt reading at the plug that attaches to the motor on the Window regulator. That reading would be the same at the back of the switch also. I would love to know if the factory Chevy Window regulator assembly is the same as this one. For instance, inside the motor is just cork screw type rod or shaft that contacts a plastic shaft, sitting perpendicular to each other. It seems like this would easily wear out if any pressure was applied to the window. I can see other problem also with this shaft slipping and grooving out the plastic shaft. In my opinion, poor design. Tomorrow I will attempt to take the window motor off, and test the free-play of the window. I’m going to clean the weather stripping and then put in a new power cord plug.

Well, I finally got this problem fixed. It turned out to be a bad connection or short circuit in the wiring at the power plug connector…(in the door wiring). After taking the window regulator motor off to test the free-play in the window…I hooked up just the motor to the power plug. It ran great for several minutes until I tilted the wires to one side. Then …no response to up and down from the switch. Some where inside the PED 3 power connector (built into the door)their was poor contact or a short. Thanks for all your help guys.

One important gotcha I learn from fixing this window regulator was not to force and electric probe into the power plug or the switch for the window. On the back of the switch and power plug are prongs(terminals) and by pushing an electric probe into these will damage them forcing you to replace them. I tried bending them back to position but this didn’t work. After damaging both the power plug and window switch terminals I have dealt with the switch intermittently not working at times. This also happened originally to the power plug, giving me the false diagnostic of a bad Windows regulator. I was able to buy new terminals and a new power plug for under $3 but would not ever want to go through the hassle of troubleshooting this problem again.

Checking automobile electrical system circuits for voltages,continuity,etc takes technique and a gentel touch.

Don’t resort to forcefull backprobing and don’t resort to piercing the vehicle’s wiring.

I know my advice is like closing the barn door after the horses are out, maybe others will benifit.