Power Window Relay Conversion

Chris825

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Looked around on here a bit and didn't see anything, so I'm asking if anybody knows of or has a good tutorial on relay conversions for power windows. I believe it's where you put some sort of relay or regulator in there and then wired directly to the car battery?
 

Ken B

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I bought some from LMC truck, if you are looking, sorry I have not installed yet so I can not help with install assistance.
 

Doppleganger

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There is an issue with the LMC kit I have read about on other sites. This guy figured it out and corrected it. He offered his diagrams if you emailed him. If you cant find it, I'll post them. I PM'd him awhile ago and he emailed it to me. I'm going to just make my own harness.

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Here's the diagram of what he did:

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RoryH19

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I built my own harness and relay setup for my k5. Definitely faster than my r10.
If the above doesn't work, let me know and I'll find my old notes.
 

Juan Cano

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Question with these relays; can I do the power window relay conversion AND also do the same for my headlights? It won't kill my battery?
 

Camar068

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Question with these relays; can I do the power window relay conversion AND also do the same for my headlights? It won't kill my battery?
When you do this it will actually be less of a "load" on your battery. Old wiring tends to add "load" on the circuitry.....which you don't want. Adding a load is like adding more lights/motors. With the relays you use the old wiring to control the relay....which switches direct battery power to the light/wiper etc. Just make sure your wiring to the light/wiper is the correct size.
 

Camar068

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Question with these relays; can I do the power window relay conversion AND also do the same for my headlights? It won't kill my battery?
to add to the above, by eleminating old wiring, going directly to your lights, door locks, windows, etc utilizing a relay.....your decreasing the load because they are "directly" connected to the battery....eliminating old wiring, connectors, etc. Your original wiring will only have to control a pretty small load (the relay).
 

Raider L

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@Chris825,

I don't want to sound ignorant, but why are ya'll doing this conversion? What's wrong with the original wiring/switch? Why would you want everything going straight to the battery? Isn't it making it there anyway through the harness?
 

Juan Cano

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@Chris825,

I don't want to sound ignorant, but why are ya'll doing this conversion? What's wrong with the original wiring/switch? Why would you want everything going straight to the battery? Isn't it making it there anyway through the harness?
In the forums and other people say that if you do this for the headlights for example, you get a much brighter headlight beam, and more consistent. On the windows, it says windows will go up and down faster. I am looking into this because the previous owner has done some bad hacking where one of the windows seems to be powered through the battery but also somehow connected to my headlights? So if I'm going in to start taking stuff apart I might as well replace the wiring. LMC sells the headlight harness for $22 and the window one for $44 (both windows).
 

Juan Cano

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This is why I am looking into the upgraded harnesses for headlights and windows. My driver side window, which works sometimes, I noticed previous owner added power cables (probably because it stopped working) and it's hacked together with the headlight switch and goes straight into the battery. At least they put a fuse. This used to have a bumper mounted LED light that was also powered out of this. So trying to clean it up and thought might as well do the Relay upgrade.
 

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Bextreme04

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@Chris825,

I don't want to sound ignorant, but why are ya'll doing this conversion? What's wrong with the original wiring/switch? Why would you want everything going straight to the battery? Isn't it making it there anyway through the harness?
The old wiring and switch configurations add a ton of resistance to the circuit and are damaging to the switches. When you convert to using a relay with power coming through a larger gauge wire directly from the battery, you remove resistance(that converts voltage to heat) and allow the windows to operate faster with less draw from the battery. It also prevents the large current arcing the contacts on the window switch and wearing it out prematurely. It is a much more reliable and efficient way to manage the electrical system.
 

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