Recently my rear window started to not work at various times on my 90 4runner. If I hit the switch a few times, it would start to go. Then it stopped working, period. Now have nothing from the key or switch. The relay is clicking so that should be fine. The rear wiper is parked and I bypassed the lockout button. Theoretically, if I run a wire from the battery to the rear motor plug, it should go up or down. If nothing happens, then the motor is shot, correct?

 

I'd try popping the rear panel off first and taking a look at the wiring harness connector to see if it were loose or damaged in any way.

 

Keep us posted Kernel, mine just started acting up exactly like you say. I've noticed it works better when the engine is running, hopefully just corrosion?

 

Go to www.4crawler.com and read all his stuff about rear windows. All kinds of things could be wrong.

 

I took the cover off and everything seems fine. Then I ran a wire direct from the battery to the motor plugin and nothing. So I guess the motor is finished.

 

I had the same problem on my 90 4runner. I went inside and took out the regulator and motor. Kind of hard for the regulator to stop working unless it gets rusty or something breaks and you can obviously see that. Did what you did and hooked the battery directly to the motor and nothing. I went inside the motor and noticed that the big gear driven by the worm had a bunch if crap around it and it turned out that some gasket or ring had broken and got stuck inside. I cleanerd it out, lubed it and then it worked fine. Sometimes I've had the wires to the brushes get caught. The window isn't great but it works. Hope this helps.