power window relay mod

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454-k10

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Like @Snoots says, What you have is much cleaner and I think much better quality than you would get elsewhere. The guy dose quality work when you can actually get what you paid for.
Totally, these are very nice.
 

454-k10

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I hate to be “that guy” but I’d skip the auto up feature.

Vehicles with auto up windows have sophisticated electronics to stop and reverse the window if something prevents the window from going all the way up. This started years ago with a sunroof lawsuit, apparently a kid got his neck stuck in the sunroof and suffocated.

If you look at power window switches today, you notice they all have buttons that have to be lifted instead of pushed to make the window go up. All because of of the sunroof lawsuit.

Maybe you don’t have kids, so this isn’t relevant. Or maybe your dog who like to stick his head out the window while your driving, who knows? Just something to consider.
These don’t have auto up or down function. I didn’t want to pay for that at the time
 

Ontheboulder

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I was wondering if someone could help me out. Im wanting to do the power window relay mod, my problem is im not positive on what wires to tap into and what not. could anyone help a brother out and let me know what wires do what and which ones i tap into. It would also be a huge help if you could include pictures or let me know which wires go to where on the relay. sorry about the noob question and i appreciate the help
howdy!! I just did the relay mod for the power windows on my 87 gmc. LMC sells a kit and it is very easy to hook up, worst part is fishing the wires thru the door boot into the cab, I used a coat hanger and had good luck. It works very well!
 

jksef1984

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Hey everyone I just installed one of those kits from LMC in my 84. At times it works great then out of nowhere I pop fuses. Any ideas what may be the issue?
 

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Check your wires from the cab to the door. Usual suspect is damaged wire on either end of the boot.
 

mibars

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I'm also fighting slow power windows.
Greasing the guides helped, however windows are still too slow. Windows go noticeably faster when controlled from the door switch than from the master switches on drivers door, so the issue is related to lenghth of wires and the fact that both ground and power must make it's way through master switch. I did a test and run a passenger window by connecting a power supply directly to regulator wiring and at 12 V it goes as fast as it should, at 14 V it is actually faster than most car windows I know. The current draw varies around 6 to 8 amps.

I couldn't find a good schematic for that relay mod so I made my own. I figured out that a new 12 V wire may not be needed, as the pink wire should be providing good 12 V power, as it goes straight from fusebox, however a new ground will be needed, as the doors are grounded only through the hinges.

I'll start by converting my slowest window and see how it will work.
 

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mibars

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Relays added and what a difference it makes!
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hoagster

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Just giving you some crap... Lol. You talking vulcanizing tape? This stuff?
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We called that F4 tape in the Airforce!
 

vr1967

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This is how I’ve always wired the window pair of relays. Not my drawing, was sent to me years ago. So unsure of who to give actual credit to.

You must be registered for see images attach

Remember when power is supplied to one side of the motor, the other wire is the ground, hence the reason they are wired this way

If relay 1 is down, it window switch is toggled to lower the window, power will come from the switch to relay 1 terminal 85, which activates the relay, basically pushing the lever from term 87a to term 87, which directs 12v from the junction block to the motor.

Relay 2 is not activated so term 30 goes to 87a which is ground, so it completes the circuit.

Let off the window switch, both go to ground, stopping the motor.

If you then want to go up, power from the switch is sent to relay 2, supplying power to the other side of the motor, with relay 1 now being the ground side
 
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82sbshortbed

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That's Greek to me. Lol

I'm sure smarter people will appreciate it tho.
 

Snoots

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You want auto UP and DOWN? Go to the boneyard and find a late '80's - early '90's Pontiac Grand Prix, Grand Am, Buick LeSabre; etc. If they have it, it is located behind the drivers door panel. Small rectangular black box. Grab it and all the wire you can get with it. Usually about 3-4 inches. They are ONLY in the drivers door; 1 per.
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squarenorth

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SO, I have hooked two relays on drivers side door(also passenger door is hooked identically) this way as pictured:
30:is window motor
85:is ground to bus bar
86:is switched power 12V
87: is 12V from battery(seperate power wire from factory)
The only factory wire I cut were the two going to window motor.

This situation didn't work when I hooked up the battery and tried it. SO I switched the 12V wire(new wire) from 87 to pin 30 on the relays. This still didn't work. I also hooked up a seperate ground wire from factory ground which runs to the (ground) bus bar on firewall.

I am hoping someone can help, sorry to kick a dead horse but I really have tried to sort this out.
Thank you.
 

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vr1967

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SO, I have hooked two relays on drivers side door(also passenger door is hooked identically) this way as pictured:
30:is window motor
85:is ground to bus bar
86:is switched power 12V
87: is 12V from battery(seperate power wire from factory)
The only factory wire I cut were the two going to window motor.

This situation didn't work when I hooked up the battery and tried it. SO I switched the 12V wire(new wire) from 87 to pin 30 on the relays. This still didn't work. I also hooked up a seperate ground wire from factory ground which runs to the (ground) bus bar on firewall.

I am hoping someone can help, sorry to kick a dead horse but I really have tried to sort this out.
Thank you.
What is 87a hooked to? It should be ground (2 grounds per relay 86 & 87a) if you used the drawing I posted about 3 replies above
 

squarenorth

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I was not using that drawing, 87A is hooked to nothing. Its the only empty pin.
 

vr1967

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I was not using that drawing, 87A is hooked to nothing. Its the only empty pin.
You don’t have a ground to your window motor. Power goes thru the relay on one side and the other wire is grounded thru the relay on the other side to complete the circuit.

Try wiring them like I show above and they will work. I’ve been doing them that way for at least 20 years
 

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