Matt16

My back window was slow going up and so I called Toyota. They wanted something close to $1000 to fix the rear window JUST FOR PARTS. This is how you can fix the relays properly for about $15. While the relays do wear out, often its the motor as well. Luckily, you can fix that for cheap as well. SEE HERE: https://www.yotatech.com/forums/f116...cement-209572/

Note: I've added an extra step, silicone spray rubbed on the rubber runners (on the body and in the tailgate) really helps the window out.

Parts and Tools

• SANYOU SRD-S-112D replacement relays x2 or x4 if you replace the rear defogger and wiper relays
• rosin core solder
• utility knife
• soldering iron
• solder sucker
• white lithium grease
• Philips screw driver
• 12V power source to test you motor window
• some wire to jump the window motor
• silicone spray

Symptoms
Back window was slow to go up but went down fast enough. It would close have way at a reasonable speed them slow to a crawl as if the motor was really straining. When the engine was on, the window would usually make it to the top, but not always. When the engine was shut off, I had to help the window up to the top with my hand.


Diagnosis
I removed the carpeted panel on the tailgate and removed the six screws holding the black metal panel underneath. This is all very self evident when you start taking it apart.

This is was you will see when the panels are removed.


I then unplugged the motor from its blue connector. The rear window goes up and down by switching the + and - terminals via a relay which will be discussed later.

I jumped the motor by taking spare 12V battery and touching it to the wires in the plug (see below). The motor worked perfectly in both the up and the down directions. I thus determined it was not the motors that were to blame for the slow back window.


The Problem
First off, some background info. The rear window motor circuit is energized via a relay. A relay is a simple electrical switch that when a first circuit is energized, it completes a second circuit.

In this application, Toyota used a 6A relay when it seems they should have used a heavier duty relay of 10A or so. After time, the contacts where the second circuit is completed wear out and no longer conduct electricity as well. Thus, the motor does not receive enough power to raise the window.

The Fix

Lubricating the tracks/ runners
About 8 months after I changed out the relays, the window stopped powering all the way to the top again. I won't bore you with the details of my frustration, but after some though, and some questions, I used silicone spray on the rubber runners inside the tailgate and on the body. These are the little tracks that guide the window. I used my finger to rub the spray into the groove and then tried the window. It was amazing the difference it made, perhaps as much difference than the relays.


Window control module relays

The control module is located by the tailgate on the driver’s side. It is just back from the storage compartment. Pull back the panel and you will see two bolts connecting the module to the body. Unbolt, unplug and remove the black box. Here’s a pic of the location with the module removed, and the connector showing (white rectangular connector to the left of the cubby about halfway down the cubby).



Here is the black window control module (relay box):

P2030080.jpg?t=1202697162

I tried cutting the tops of the relays off and cleaning the contacts, but this did not work at all. I wouldn't bother. Some people have simply swapped the wiper motor relay with the window motor relay. The wiper relay is in better condition usually because it is not used as heavily. It would probably work, but your wiper would be compromised.


I decided to replace the relays as they were cheap and as it turns out, easy to find.

I called around to see if I could find replacement repairs from the OEM (Omron). However, I was told that these Omron relays were specially built for Toyota and you cannot buy them. The electronics part store (Main Electronics in Vancouver, BC) were very helpful and found a 5 pin relay that is smaller and would fit. It also has a higher amperage rating of 10A which should it should last the life of the truck.

Open the black box up and you will see the relays and assorted circuitry. Going from left to right the functions of relays are
1. WINDOW UP 2. WINDOW DOWN 3?4? (Please tell me if you know which is which)



Basically, you have to remove the two relays (black boxes) closest to the black cylindrical bit on the left side of the photo below. I used a spring loaded solder sucker. I then soldered on the new relays, which are smaller, but heavier duty.



Here are the new relays, they're made by SANYOU. The part number appears to be SRD-S-112D. They are smaller than the OEM relays and fit just fine. The pins are in the same positions and its simply a matter of removing the old and soldering in the new relays.


Reassemble and now you should have a working rear motor. My window goes up in about 5 seconds now. Anyways, it works a lot better and didn’t cost much.


Supplementary repairs

Grease the runners where the motor contacts the window with lithium grease. This also helps protect against rust, though it’s probably rusty already.



While you're at it, I'd replace the other two relays as well on the board as well. One controls the rear wiper motor and the other I think controls the rear defroster although it could control the function that lifts the wiper off the glass...not sure. Might as well replace them while you're at it though.

kellhammer

Matt
This is a problem I have been having with my 93 4runner. Goes down no problem. Doesn't want to go back up. Soemetime I wiggle the rear wiper or the key and it comes back to life
Do you have a part number and manufacturer from the store you bought the relay?. Was it the same size because I read some replacements don't fit when you go to install the board in the black box..

kellhammer

Great write up by the way. Very informative!

Denk

I am definitely giving this one a shot. I constantly have to manually help the window going up.

Part numbers for the relays would be a great help. But I don't think it would be a huge problem to take out my own relays and take them to the eltronics storeto find a match.

DCS

I'm a bit confused by the photos and text.

Did you mean "left to right" in the 6th photo?

Did you mean the "black cylindrical bit on the LEFT side" of photo 7?

Are the Sanyou relays in Photo 8 the window relays you replaced?

Just out of curiosity, what's with the black cover over the other relays in photos 7 & 8?

Thanks!

DCS

Also, does the carpeted cover just pop off, or is there a trick to it?

Thx!

Matt16

DCS I meant left, pardon me. I used a different set of photos than I originally intended.

The carpeted cover just pops off, I just grabbed it by the corners and yanked. Not difficult.

Denk and Kellhammer, I've edited it now:

Here are the new relays, they're made by SANYOU. The part number appears to be SRD-S-112D. They are smaller than the OEM relays and fit just fine. The pins are in the same positions and its simply a matter of removing the old and soldering in the new relays.

Matt16

DCS, the black cover over the two other relays is electrical tape. I opened them all up in order to see which were involved the operation of the windows and to see if I could clean the contact. I could not do so, thus I replaced them.

Matt16

Let me know if this works on your 4Runner when you do the mod, I hope this helps.

DCS

Thanks for the writeup!

Tonight:
I removed the carpet cover, black steel plate, and plastic dust cover. With the tailgate down, I used a battery on the blue plug to move the window "up". I cleaned the window-slots on the sides and also the two lift runners with walmart carb cleaner. I also cleaned the window slots on the cab. I blew everything dry and lubed all the window slots with silicone spray lube. I lubed the window runners with spray teflon chain lube (set's up to a light grease film).

Put it all together, and it's better now. Using only the key in the tailgate switch, the window goes up at acceptable speed, without assisting push. Before this cleanup, I was having the same problem described by the OP.

However, it's still slower than when the battery is hooked straight to the motor. So I'm definitely having some current loss through the harness and relays.

If it gets bad again, I'll try the relay swap.

Matt16

Swapping the relays could be done in less than an hour, forgot to mention that.

kellhammer

I've looking here in the US for the Sanyou part

Just found a company over the internet TESTCO
email sales@testco-inc.com They have the relay for 4.95 each. Minimum order is $25.00

Can't wait to fix this F#$%ing thing. Been a P.I.A for years

Matt16

I called up a local electronics parts store and described the relay. Here's the description of the relays used:

12-volt miniature automotive
PCB relay with 5 pins
320 ohm coil
approximate OEM dimensions: 22mm long X 16mm wide X 15.5mm high

From this site: http://www.geocities.com/dkwalker/te..._relay_fix.pdf

Denk

Omron automotive carries a relay very close to the stock one represented in the above attached write-up. I have a couple of calls into some distributors to see if they carry or have something comparable.

kellhammer

I just finished making this repair using the switches I got from TESTCO. Works perfect. Total time to repair was about an hour. The desoldering iron I got from radio shack ($10.00) was essential. Watch out when you suck the solder out that you only squeeze the away from the work. I splattered my circuit board by accident. I went over with magnifying glass to make sure I didn't connect a circuit that wasn't supposed to be connected. The rear window on my truck has not worked correctly for years. I feel like it's a new truck. Great fix total cost about $40.00

Matt16

You used switches instead of relays?

kellhammer

Sorry, I meant to say relay not switches. I used the Sanyou relays described in this thread

UKrunner

A direct cross to the Omron relay is a NAIS JS1-12V-F. It's available at Digikey.com and here is a link to it.

http://search.digikey.com/scripts/Dk...me=255-2080-ND

I have literally thousands of these out in the field in automotive applications I've designed, and never had one fail. I use them in remote locking, power window, remote electric bed covers and alarm applications.

Infact, I'm posting this because I just found this thread after doing this repair with these relays myself.

Matt16

What is your field of work?

thook

I tried to do this repair to my '86 several years ago when I found 4crawler's website. He explained how to do it and where to get relays. I got some at Radio Shack.....a big electronics chain in the U.S.

Anyway, my repair attempt didn't work out. I didn't know much about soldering and I damaged the circuit board from the heat. Engggh.....now that I know more about soldering, I'd like to try again, but I'd have to get another relay board first.

So, a belated thanks for the write-up, Matt16. Very good job. I'm inspired to make another attempt. I've never had the rear wiper working and I'd like that little feature.....damn it.