How to send power to window switch for testing?

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PhotonFanatic

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I'm trying to fix my slow passenger side window in my 87 truck. It's slow going up and down, and it needs a person to help it go up. I have already replaced the window motor and the regulator with new AC Delco stuff. So we can rule that out.

I need to test and see if it's a poor voltage problem, or a frictional drag on the window itself. Or both. Does anybody know what each colored wire does, for the passenger window switch? Then I'd know exactly where to send power with the Power Probe. That would tell me the answer.

If the window is fast when supplied with power directly, then I don't have a frictional drag. I don't really want to pull all those seals out of there if it's not necessary.

I searched and found this, but I think it's for an 83 model. Maybe it's the same as 87? Anyway I'm not so good at reading electrical schematics. Looks like the passenger side switch is at the very bottom but I'm not certain where to plug in the volt meter prongs to test the voltage. Or where to send power. Thank you

 
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AaronW

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On my 89, it's the black and blue wires that run it up and down.

Aaron
 

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Try silicone spray first. Helped a lot on mine. Just spray the channels with the window down. If the door panel is off you can also spray the bottom of the channel.
 

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TotalyHucked

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On my '85, the dark blue wire makes it go up and the dark brown wire makes it go down. I literally just did this yesterday lol.

If you can't get it all to work well (I couldn't on mine, everything just died all of a sudden), check out Nu-Relics. I just finished my install yesterday and man, these things are AMAZING. Even with the key off they fly up like a modern car. Well worth the money and was the easiest install I've done in a long time.
 

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Try silicone spray first. Helped a lot on mine. Just spray the channels with the window down. If the door panel is off you can also spray the bottom of the channel.
I can't help with the writing color, but it's a pretty rare day that it would be high resistance in the wiring somewhere. Of course it's possible, but when I see a slow window problem at the shop it's always mechanical drag, or a weak motor. ACDelco is good stuff but not infallible, so don't rule that out completely. silicone spray isn't always the forever fix we'd like it to be, but it's simple to do. Hose the window channels down with it, if it's better you have found the problem.
 

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I'm trying to fix my slow passenger side window in my 87 truck. It's slow going up and down, and it needs a person to help it go up. I have already replaced the window motor and the regulator with new AC Delco stuff. So we can rule that out.

I need to test and see if it's a poor voltage problem, or a frictional drag on the window itself. Or both. Does anybody know what each colored wire does, for the passenger window switch? Then I'd know exactly where to send power with the Power Probe. That would tell me the answer.

If the window is fast when supplied with power directly, then I don't have a frictional drag. I don't really want to pull all those seals out of there if it's not necessary.

I searched and found this, but I think it's for an 83 model. Maybe it's the same as 87? Anyway I'm not so good at reading electrical schematics. Looks like the passenger side switch is at the very bottom but I'm not certain where to plug in the volt meter prongs to test the voltage. Or where to send power. Thank you


the later system alternates the power and ground to make it go up or down

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gmbellew

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On my '85, the dark blue wire makes it go up and the dark brown wire makes it go down. I literally just did this yesterday lol.

If you can't get it all to work well (I couldn't on mine, everything just died all of a sudden), check out Nu-Relics. I just finished my install yesterday and man, these things are AMAZING. Even with the key off they fly up like a modern car. Well worth the money and was the easiest install I've done in a long time.
did you use their switches or keep the OEM switches?
 

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I would be reluctant to use lube just because of the dirt it collects over time, I would remove the window motor and see if the window moves freely by itself. The path beyond that should be obvious based on weather or not the window moves freely.

I am dealing with the same problem. I rebuilt both window regulators, all new track glides and window track/felts, new motors. I didn't pay close enough attention doing the first side and had a little resistance that I thought would break-in over time. It didn't. I have to take the passenger side apart again to fix what I missed. My mistake was using glue that expands (Gorilla glue) it expanded just enough to pinch the gap on the window track felts, and create slight resistance.
 
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TotalyHucked

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did you use their switches or keep the OEM switches?
They supplied their basic OE replacement switches. I may upgrade to the nicer ones later on. But for now, they work fantastic and everything looks OE.
 

gmbellew

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They supplied their basic OE replacement switches. I may upgrade to the nicer ones later on. But for now, they work fantastic and everything looks OE.
did you replace the wiring harnesses, or keep the OEM wires and just use their switches? it looked like their switches required their harness. but I wanted to verify
 

PhotonFanatic

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Try silicone spray first. Helped a lot on mine. Just spray the channels with the window down. If the door panel is off you can also spray the bottom of the channel.

Unfortunately it had no effect. Makes me think I got lucky on the driver's side. Works great after installing a new AC Delco motor and regulator.

On my '85, the dark blue wire makes it go up and the dark brown wire makes it go down. I literally just did this yesterday lol.

If you can't get it all to work well (I couldn't on mine, everything just died all of a sudden), check out Nu-Relics. I just finished my install yesterday and man, these things are AMAZING. Even with the key off they fly up like a modern car. Well worth the money and was the easiest install I've done in a long time.

Looks like I need to feed power to the brown wire, and then the blue wire. Someone said the pink wire also carries power but I think it's just the main feed to the switch. Then electricity goes from there to the brown wire or the blue wire, depending on whether you press up or down.

But thanks for the recommendation, I didn't know about Nu Relics. If I can't make this work I might just go with them.
 

gmbellew

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Unfortunately it had no effect. Makes me think I got lucky on the driver's side. Works great after installing a new AC Delco motor and regulator.



Looks like I need to feed power to the brown wire, and then the blue wire. Someone said the pink wire also carries power but I think it's just the main feed to the switch. Then electricity goes from there to the brown wire or the blue wire, depending on whether you press up or down.

But thanks for the recommendation, I didn't know about Nu Relics. If I can't make this work I might just go with them.
pink is constant power with key on. ground always goes back through the master switch. power is switched between the other two wires to move the motor up or down with the switch. one of the wires will be power and one will be ground. it reverses when the switch is reversed, moving the window the other direction. if you have 12v on pink, the switch is getting power. if the other window works, ground is good from the master switch to the bus bar by the e-brake. check voltage to ground on the blue and brown wires when moving the switch up or down. if it is a solid 12v, then the issue is a bad motor or something is binding badly.
 

TotalyHucked

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did you replace the wiring harnesses, or keep the OEM wires and just use their switches? it looked like their switches required their harness. but I wanted to verify
I *think* you could probably run it with the factory wiring, technically, but I wouldn't since it's all 30+ years old and small gauge. Their harness is super high quality, thick gauge wire, nice loom and quality connectors. I was able to completely de-pin and do away with the factory wiring, which I think was my problem all along. It has one ground on the driver's door (I used one of the bolts that mounts the regulator and just cleaned the paint underneath) and one power wire that I ran to my switched power distribution block under the hood.
 

PhotonFanatic

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pink is constant power with key on. ground always goes back through the master switch. power is switched between the other two wires to move the motor up or down with the switch. one of the wires will be power and one will be ground. it reverses when the switch is reversed, moving the window the other direction. if you have 12v on pink, the switch is getting power. if the other window works, ground is good from the master switch to the bus bar by the e-brake. check voltage to ground on the blue and brown wires when moving the switch up or down. if it is a solid 12v, then the issue is a bad motor or something is binding badly.

So if I take your meaning, you're saying there's no need for me to run power to anything. Just check those two grounds?

Sorry about all the noob questions, I'm something of an electrical newb.
 

gmbellew

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So if I take your meaning, you're saying there's no need for me to run power to anything. Just check those two grounds?

Sorry about all the noob questions, I'm something of an electrical newb.
 

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