Power window motor?

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Grit dog

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Quick check before ordering a new drivers side window motor.
Have power to the switch. Power to the window motor plug as expected on/off with the window switch.
No other possibilities, correct? Just a smoked window motor?
 

Ricko1966

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If the motor is getting power and ground but doesn't turn it is the motor. Disconnect the plug supply power and ground with jumper wires.do it this way,unless you understand that the switch,changes polarity to the motor. So using switch for power may result in a smoked wire,if your ground is in the wrong place,wrong time.
 
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Grit dog

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If the motor is getting power and ground but doesn't turn it is the motor. Disconnect the plug supply power and ground with jumper wires.do it this way,unless you understand that the switch,changes polarity to the motor. So using switch for power may result in a smoked wire,if your ground is in the wrong place,wrong time.
Yes I did thanks.
Checked assembly was cont to ground. And only checked for + on the 2 wires, - grounded to the body.
Thanks for the heads up though!
 

Ricko1966

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Yes I did thanks.
Checked assembly was cont to ground. And only checked for + on the 2 wires, - grounded to the body.
Thanks for the heads up though!
1 wire going to the motor is a hot the other is a ground switch reverses polarity on those 2 for up or down . So you need to provide a power to 1 terminal at the motor and a ground to the other. Then flip flop them. Case is not the motor ground
 

Grit dog

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1 wire going to the motor is a hot the other is a ground switch reverses polarity on those 2 for up or down . So you need to provide a power to 1 terminal at the motor and a ground to the other. Then flip flop them. Case is not the motor ground
Ok I was off in my thinking. Although I thought I checked the case to ground. Either way, have + power on opposite pins based on switch direction and when pigtail is plugged into window motor can hear a click when switch is pressed.
Still a bad motor I believe.
Thanks again for the help!
 

Camar068

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if in doubt, run a positive and negative directly to the motor connection from a 12V battery. then reverse the wires just in case while ur there. Helps if you have an old plug to sacrifice to extend it out the door.
 

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My fancy winders have decided to start giving me problems now. I think I might've pinched a wire somewhere under the dash when I put everything back together for the console/stereo:893Chainsaw-Smilie-
 

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I re-rubbered all the seals, gaskets, window guides, wipers (door window wipers) and using stock motors --- they run very well without any extra relays.

The rear window is another thing however and I used a tap off of the 0Ga welding wire I ran to the back bumper near the 7-pin RV jack to add power to that rear window motor.

It is now a very quick guillotine.

Long runs of wire and DC low-voltage electricity are a problem.
 

bucket

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1 wire going to the motor is a hot the other is a ground switch reverses polarity on those 2 for up or down . So you need to provide a power to 1 terminal at the motor and a ground to the other. Then flip flop them. Case is not the motor ground

if in doubt, run a positive and negative directly to the motor connection from a 12V battery. then reverse the wires just in case while ur there. Helps if you have an old plug to sacrifice to extend it out the door.

I could be wrong, but I thought the 70's window motors were not wired like the later ones. The window motor gets it's ground through the case, then both of the wires are 12+. One for UP and one for DOWN. I don't believe that it's a switching ground system.

I know for sure that's how the K5 and Suburban tailgate window motors operate though, and they were used all through production, including the 70's. Iirc, they are similar in design and use the same plug as the 70's pickup power window motors too. Although I haven't messed with them in such a long time, and only a time or two. It's not a common option to find on the older trucks.
 
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Ricko1966

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I could be wrong, but I thought the 70's window motors were not wired like the later ones. The window motor gets it's ground through the case, then both of the wires are 12+. One for UP and one for DOWN. I don't believe that it's a switching ground system.

I know for sure that's how the K5 and Suburban tailgate window motors operate though, and they were used all through production, including the 70's. Iirc, they are similar in design and use the same plug as the 70's pickup power window motors too. Although I haven't messed with them in such a long time, and only a time or two. It's not a common option to find on the older trucks.
Hmm thanks for saying something, I should of researched before chipping in,was working completely from memory in Kansas City, was working from memory from my AC/Delco circuits and meters class from 1981. I was so sure in my mind that's how they taught us the power window and power seats circuit. IDK if they were one way at one point and a different way at a different point. Sorry if I mislead anyone or created confusion. Thanks have a great day.
 

bucket

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Hmm thanks for saying something, I should of researched before chipping in,was working completely from memory in Kansas City, was working from memory from my AC/Delco circuits and meters class from 1981. I was so sure in my mind that's how they taught us the power window and power seats circuit. IDK if they were one way at one point and a different way at a different point. Sorry if I mislead anyone or created confusion. Thanks have a great day.

Yeah, I'm honestly not sure. You could very well be correct. I only "think" that's how it was on the older ones ('80 and earlier).
 

bucket

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I just wanted to bring it up just in case. The first time I ever tested a Suburban rear power window motor, I figured out the correct operation only after some smoke and a very warm wire.
 

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Can't tell you what year the change happened?......but the older style window motors are a HE!! of a lot more expensive than the newer style!!
 

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