steveaus

I've got a 1990 down in Baja that I drive around with and that will never see the U.S. or probably a paved road again. The wiring to the rear window motor has gone bad. Probably a relay, but the local mechanic couldn't figure it out and and I didn't have time to play with the relays so a local guy ran a new wire direct to the battery. Now it's just two wires that lead to the battery and I have to open up the hood and touch them to the battery to operate the window.

So I've already decided to bypass the wiring and put in a new switch. Can anyone tell me what amp switch (or even better yet, a part number) or specs I need and what amp in-line fuse?

mental

After getting my tools stuck in the back of my runner one afternoon I spent 20 minutes wiring up the old dptp switch with some heavy guage speaker wire. It hasn't let me down since. I meant to switch it out for a relay system but life keeps getting in the way. In any case I use that window 5 - 10 times a day even in winter, works every time.

dropzone

iTrader: (6)

you can find the wiring diagram here:
http://ncttora.com/fsm/index.html

waskillywabbit

iTrader: (-1)

4crawler has a ton of rear window info on his site.

Why not take a little time and fix it right instead of bootyfabulous wiring that could burn up something else?

:wabbit2:

xxxtreme22r

x2. Wiring straight to battery etc etc it probably not a good idea. There is a relay there for a reason. Grab your favorite multi meter and wiring diagram and figure it out. If it's a relay issue then the relays are damn simple to change out.

coryc85

My '88 is fused for 20Amps to the rear window relay board, but the relays themselves are not rated that high, they are under 10Amps but I don't recall exactly. A switch rated for 10Amps with an inline 10A fuse right off the battery would be just as safe as the original relay board.

xxxtreme22r

and if the wiring chafes off the body then what? Whether or not the window is in operation or not you have constant power going through the firewall etc etc from the battery to that back window. With a relay constant power is contained in the engine bay or inside the cab near the firewall until the window is in operation.

The only "correct" but not preferred way to run directly from the battery is to fuse it before and after any body protrusions. That's actually how I have my CB hooked up. It's fused inside the engine bay as well as just before the radio so I have protection in the event that wire grounds out on the body.

coryc85

If the wiring chafes, then the fuse blows.

No, if he uses a switch he will have constant power through a fuse to a terminal of the switch, which I presume will be in the cab. Power will only go to the window when in operation.

Right, so you connected a wire to the battery with a fuse to your CB, which I think is exactly what the OP wants to do except with his window motor. I think he, you, and I are all saying the same thing. It's not at all unsafe or uncommon to connect something directly to the battery, when the proper wiring, fuse, switch, etc are used.

kooolr

I agree with the others- bypassing, even w/proper fuses or relays isn't always a good idea... i have two extra relays lying in a box in my shed. (out of a 94 & a 95) i'm unsure of fitment to your model(90?). after fighting my window for weeks- i snatched three of them from the local pullapart. also- getting AT that relay is a BS. i even have some extra body panel snaps if you need them a bag full. PM me if interested.

steveaus

In layman's terms, if I have a fuse on the line, what is the purpose of the relay? Can I just add a generic relay to my bypass wiring?

coryc85

Steve - the relay has a low current side, which uses an electromagnet to switch the contacts closed on the high current side. So basically Toyota can run a light duty switch with small gauge wire into the cab and the heavy load runs thru the relay high current side when switched. If you get a switch rated for enough current, you don't need a relay. You would still want a fuse even if you use a relay.

No affiliation, just googled and found these switches: http://www.wiringproducts.com/contents/en-us/d130.html

And specifically this switch is ready to go, it's a momentary double pole, double throw so you hold it one way and your window goes up, let go switch goes back to the middle, hold the other way and window goes down.
http://www.wiringproducts.com/contents/en-us/p4055.html

steveaus

Bought the switch, thanks. What amp fuse and what gauge wire should I be using? Any other easy things I should add? I need to buy it all here and bring it with me to Baja.

coryc85

Steve - well since the relays on the OEM board are only rated for 10A, I would say that a 10A fuse would do the trick. As for wire gauge to use, I found this neat chart that shows what gauge to use depending on the length needed since wire has an Ohms per foot rating. Here is the chart http://www.engineeringtoolbox.com/am...uge-d_730.html

The way I read it, if you need to go 15 feet, at 10Amps, you need 12 gauge wire.

steveaus

Thanks, Cory.

Duffdog

You know, you could always find an old school alarm installer to wire up 2 relays for you in about 10 minutes. Then you could use any switch you wanted without fear of fire. General practice is to fuse the main power wire within 12" of the battery post.

The main advantage to using relays is that the relays can handle substantially higher current and generally make the window motor work better. I would wire up a couple bosch 40a relays for ya in no time, but you are on the other side of the country!

SeeBeeAre

ok ok ok i know there are a couple of threads here and im having a rear window issue!!!! after cleaning the switch i still had the same issue.... after chasing wires i wish there was a diagram to show the different switches and stuff in series with the circuit..... now my window ended up being the connection at the adapter right befor the motor, the wire came out of the connector just enough to make it act funny.... I fixed that wire and am going camping will let you know how it turns out

Gutpile23

So I'm bypassing the rear window relay on my 89 4runner and running a fusible line off the battery, but I got a few questions here though. The OEM switch is dead, so I got a new switch and ran it from a charger to the window motor and everything works fine, the problem is my rambunctious dogs. I can see them hitting the toggle switch (it doesn't matter where I put it in the cab) and running the battery dry. So I'd still like it to run from the ignition so the power's off when I'm gone. But when I test the voltage at the original lines, what I get is
8.9 vdc at R-W
8.9 vdc at R-Y
and 8.9 vdc at Blue-R with neg. at ground.
So none of the existing is running the motor. AND, when I tried one of the combos the head lights went out, there was, what sounded like an electric motor running, then dying, when I tried to turn them on again.
This is my first time diving this deep into Toyota electrical, and I need some help. Cheers.

Green 88

Cory knows electrical that’s for sure…

... and so does Duffdog.
Even if you had a switch that could handle the 10 amps for the motor, relays would still allow the motor to work better.

On most common aftermarket relays there are numbers next to the spade terminals. You’ll need two relays and they are both wired the same. One relay will be for down and the other relay is for up. The two terminal 30 will go to the motor (each motor wire has it’s own relay). Terminas 87a go to ground. Terminals 87 and 85 go to fused power (10 amp should be good) (constant 12V if you want the window to be able to go up and down with the key off or to ignition 12V if you only want it to work when the ignition is on). Terminals 86 goes to your switch. Your double throw momentary switch will have 3 wires going to it, the middle wire will go to ground, and the two outer wires will go to terminal 86 of the relays, each outer wire having it’s own relay.

I don’t know the year and model of your truck. I don’t know where the red/white, red/yellow, and blue red wires are that you are checking. You need to find where exactly the voltage drops to 8.9V. Trace the wire towards it’s power source until you find where the voltage goes to 12V.

jswizz

Hey there. Do a google search for rear window relay , pick cheap tricks . I think its a 4crawler page and there is a whole write up on soldering the posts inside the realay to another and Bingo . its a bit time consuming figuring the colors of the wires but it solved my issue greatly .and you still use the relay with a simple toggle froom craken parts store .

Gutpile23

Oh. Ya. It's an 89' 4runner SR5. And the wires that I posted about are coming off the window up/down switch. I did find a straight +12vdc line, that in the diagram says runs from a 20amp fuse into the relay, but it goes dead when I turn the key. ????
I'm starting to trace back now, because I might as well do it right while I'm here. I need a better manual though, and there's no terminal #'s on the relay, so I'm lost reading your post. But what you're saying is exactly what I want.