To start: I'm an electrical dummy.
That settled, 1990 4Runner driver window is not working. I pulled the switch panel from the door, disassembled, and cleaned all contacts. All other switches in the panel work, just not the driver window. I assume this is because of the "auto" function circuit board. It looks like there has been water in in there at some time, and I suspect there is a failure on the board. Does this sound correct?

I see used switch assemblies on eBay for $15 w/ free shipping - I assume it's not worth much effort to try and troubleshoot this much further... except to possibly try and manually bypass the switch with a jumper at the connector pins and confirm the window *can* work and that the switch is in fact the issue?

Thanks for your help...

 

You may want to check the electric motor on your window regulator. Does it make any sound at all in the door when you press the switch? If your regulator checks out ok then I'd look at the switch. And most salvage yards will sell you one for around $5-10.

 

Agreed jumper the motor to make sure it's working, these motors do fail especially drivers door which sees the most use.