Mark, and anyone else on the planet looking for answers to the number one bitch about 4Runners.
Please Note: This is only 100% accurate for Aug 90 4Runner. the controller box changed from time to time - though I suspect it will be similar for all series 2 4Runners.

If you are getting a "CLICK" from the relay box when you operate the switch / lock, it means that all other interlock systems are okay. If you are NOT getting a "click" from the relay board, it means fuse blown / Circuit Breaker tripped, or one of the many interlocks are not functioning. For those who are interested, these include:

1. Window Up switch - activated when the window regulator reaches the Up position - located adjacent to window motor.

2. Door lock switch - Turns on that little light on the dash when the tailgate is not locked - located to the right of Window up Switch, connected to lock button.

3. Tailgate Closed - Activates when the Tailgate is closed ( Like it wasn't obvious ) located at the lock mechanism itself to monitor the position of the latches. NOTE: If these are cheated and you operate the window with the tailgate in the horizontal position you WILL break the rear window if you do not support it adequately. DON'T SAY YOU WEREN'T WARNED !!!!!

4. Wiper Home - Detects if the Rear wiper is correctly parked - located in the wiper mechanism above the rear window.

Some of the above switches are normally open, others are normally closed, check both states before assuming a switch has failed.

All of these switches are connected to the Rear Window Control Relay located in the rear left of the vehicle ( just to the rear of the left side storage box ). This is really a box containing one circuit board, a number of relays ( Varies with year model ) and some surface mount components (mostly transistors)on the board.

If your truck passed the above test and you are getting a "click" when you attempt to operate the rear window, it is probable that the contacts of one of the relays have burnt out. The board in my 90 model had six relays - four of one type, and two of another. I felt for the source of the "click" and replaced the four matching relays (my truck is 12 years old)at a cost of $3 Australian each - $12 total - much better than $580 quoted by Toyota. This rectified the problems with my rear window.

BE ADVISED - THIS BOARD IS DOUBLE-SIDED !! THE RELAYS ARE SOLDERED ON BOTH SIDES OF THE BOARD. If you are not familiar with the techniques required to perform this task, I suggest you take the board to your local TV repair shop - might cost you $40 ( half an hour )

If shopping for replacement relays you will require the correct pinout ( it is a standard )and ensure they can handle at least 10 amps. anything less than this and you will be repeating this in a few months time.

While you have the tailgate open I would suggest that you clean the window runners and regulator gears( the two big s-shaped ones ) and apply some form of dry lubrication to the contact areas of these gears.

I also found some major probs inside my rear window motor but I'll save this fix for private email if required.

Another helpful source of info can be found at http://4crawler.cruiserpages.com/4x4/CheapTricks/RearWindow.shtml#Troubleshooting although it is aimed at series one 4runners.

Hope this has been of some help. If I can get hold of a digital camera, I may dedicate a web page to this. If you need anymore help, email me at mickclements@austarnet.com.au