Need To Make Some Repairs For A 97' Es300

[cu2cool]

Sorry if this thread is repeating any already asked questions. I just looked through the forum and didn't really find any helpful answers to my questions. I have a 97' ES300 with several problems.

First, passenger and rear right window switches are not functioning. They can both roll the window down, but not up. I do not hear any click as mentioned in the other threads. I want to try to clean the switch and see if that will fix the problem. Could anyone please provide detailed instructions on how I would be able to do this?

Secondly, I'm having the periodic "check engine" light problem where it would turn on for a few weeks and go away for a few weeks. I've had it checked out at a garage with the detector and the repair man said that it was a gas cap problem. Is there a way to fix this or a cheap way to replace any faulty parts? I think my mother had tried to have this problem fixed, but the light still comes on.

Lastly, the LCD screen has gone completely black, and the lights for most of the audio switches have stopped working. Are there any cheap websites or stores around Boston that would sell replacement parts? Are there any web sites or could someone possibly provide detailed instructions on how to replace the console manually?

Thanks in advance.