Power window Buick

[kaycee]

At witts end here on my 02 Buck Century, drivers side rear window wont roll down all other windows work . Wont roll down from master switch (front drivers side)works all other windows .Got new motor / regulator swapped it out same problem ,swapped door switch out to other side same thing no roll up on drivers rear. allso old and new motors swapped over and still wont work on drivers side. Have swapped relays around and have power all the way to motor WTH am I missing here

[Getter-Done]

Wires sometimes break where they run through the door.

They may not appear to be broken because the insulation is still intact.

[kaycee]

I got power all the way to motor on the old and new motor sand they both check out with test light.

[Getter-Done]

Have you plugged the old regulator in (Outside of the door)?

Just to see what happens.

[kaycee]

Yes it rolls up and not down on both new and old reg /mmotor will go up and down on pass. Side

[Getter-Done]

I found a wiring diagram online.

That is the best picture I can get.



So you have both up and down wires that have 12 volts?

[kaycee]

Yes sir 12 volts all the way to motor

[RustyPile]

Originally Posted by kaycee

Yes sir 12 volts all the way to motor

The switches not only apply voltage to the motor, but they also switch the polarity on the motor.. Unplug the harness form the motor and connect a test light to the 2 wires.. Do not connect the light to a ground source.. If all the switches, relays, and wiring are intact and working, the test light will light up when the switches are moved up or down.. If the test light lights up both ways, the motor is bad.. If it light up in only one direction, it's time to dig deeper for switch failure, and/or wiring failure. If ANY of the other windows work as they should, you do NOT have relay problems.

An LED bulbed test light will not work for this test. You have to use one that has an incandescent bulb in it.

[kaycee]

Ok did that light works on the up side but not on the window down ,

[Getter-Done]

Originally Posted by Getter-Done

Wires sometimes break where they run through the door.

They may not appear to be broken because the insulation is still intact.

I think you have a Wire in the harness that is Broken.

Originally Posted by RustyPile

The switches not only apply voltage to the motor, but they also switch the polarity on the motor.. Unplug the harness form the motor and connect a test light to the 2 wires.. Do not connect the light to a ground source.. If all the switches, relays, and wiring are intact and working, the test light will light up when the switches are moved up or down.. If the test light lights up both ways, the motor is bad.. If it light up in only one direction, it's time to dig deeper for switch failure, and/or wiring failure. If ANY of the other windows work as they should, you do NOT have relay problems.

An LED bulbed test light will not work for this test. You have to use one that has an incandescent bulb in it.

Great explanation.

I neglected to add the workings of the Motor with 2 wires and that one is (Power up) and the other is (Power down).

I was working on a remodel of my Kitchen.
And sneaking in to keep up on the Forum.

Originally Posted by kaycee

Ok did that light works on the up side but not on the window down ,

That wire needs power also.
The regulator grounds thru the mounting screws.

These newer Vehicles are not as simple as our 63 Impala's

[RustyPile]

Originally Posted by Getter-Done

>>>>>snip<<<<<<<<<
Great explanation.

I neglected to add the workings of the Motor with 2 wires and that one is (Power up) and the other is (Power down).

:

Getter-done, That's only partially correct.. The motor is not grounded to anything... The motor is of the "bidirectional" design, meaning depending on the polarity of the voltage being applied it can run in either direction and the switches make that direction selectable.. The two terminals are actually each end of the windings. One is positive and the other is negative.. Apply positive voltage on one of the wires and ground the other -- the motor runs "forward".. Reverse the polarity of those two terminals and the motor runs the other direction. This reversal of polarity is all done through the switches.. It's a very complicated and complex circuitry, not meant for the unskilled or faint of heart..

@kaycee... Since you have substituted known good switches, I think you have an open circuit in the wiring.. Most probable location is inside the boot that houses the wiring as it passes from the door post into the door. If you want to learn how the circuit works, send me a private message, and I'll be glad to send you the GM Factory generated troubleshooting guide for power windows. It is a step-by-step procedure and if followed precisely, it will guide you to the problem..

[kaycee]

Well crap , I was thinking that must be how the switch operates appreciate all the help and advice. I’m still trying to figure out how to work my multi meter and pinpoint electrical problems a little better, maybe the step by step will help.Again Thanks for the Help

[kaycee]

Well crap , I was thinking that must be how the switch operates appreciate all the help and advice. I’m still trying to figure out how to work my multi meter and pinpoint electrical problems a little better, maybe the step by step will help.Again Thanks for the Help

[kaycee]

So I could get a set of jumper wires and go from master switch back to door switch and see if that is broke between the 2 before I pull all that apart in the B pillar Correct ? Im going to go to recess for a day or 2

[chevyguyase]

I'm reading the posts and don't see where you've replaced the master switch. If that's so, go to your master switch. find the dark green wire and the purple wire. apply +12v to one and ground to the other. The driver's side rear window should go up or down if the rest of the circuitry is good. now reverse the jumper wires and the window should go the opposite way, up or down. You obviously have B+ and ground to the switch if the other windows work from the master switch. If you can control the window through those two wires from the master switch it almost has to be a bad master switch. Which is usually the culprit,(most used) that and the wiring going from the door to the body on the drivers side(most used). Hope this helps.

[kaycee]

Yes master was charged a couple months ago devs front switch was wore out so replaced it .The master wont operate the rear drvs either ,but will try that.