my car is 02 corolla.
power window does not work?!
As I bang the door, it works again!
however, after it park at no cover area under direct sun-light (heating for a few hours), it fails to work again.
does anyone know what causes the problem?
is the problem of the motor?!
how to fix it?!
please help!
thank you.
Many things will cause problems with the power windows. Luckily, you got it narrowed down - you mentioned that banging on the door helps and the problem comes back when the car is warmed up.
Sounds to me like it is a contact/no contact issue with the switch panel or at the window motor. Chances of it being the motor are unlikely, but always possible. To fix - you have to strip off the door panel and check all the connections between the switch and the motor.
My suggestion is to get one of the service manuals (Haynes, Chilton, Toyota, etc) and a multimeter or similar, if you don't already have them. The pinouts of the switch require more detail than what I can post here - better to see them illustrated in the book to give you an idea.
Good Luck.
1For a 2000 LE like mine I have uncovered the following parts for power windows (plus parts categories and price from 1sttoyotaparts.com):
Window Motor (Electrical , Body electrical ,Front door ,Window motor)
189.56
Window Regulator (Body hardware , Door ,Front door ,Window regulator)
56.36
Window Relay Marked 9008498031 (Electrical , Body electrical ,Door ,Window relay)
37.53
Window Relay Marked 9008087010 (Electrical , Body electrical ,Door ,Window relay)
15.47
Isn't it possible to short out this stuff when driving in the rain? I also have been guilty of using the rubber stripping between which the window rolls down/up as a squeegie! That too could have done it! 
1i have fixed the problem now!
thank you.
What did you find and how did you fix it? I have a similar problem with my passenger side rear window.
Window Motor (Electrical , Body electrical ,Front door ,Window motor) $189.56
Window Regulator (Body hardware , Door ,Front door ,Window regulator) $56.36
Window Relay Marked 9008498031 (Electrical , Body electrical ,Door ,Window relay) $37.53
Window Relay Marked 9008087010 (Electrical , Body electrical ,Door ,Window relay) $15.47
Notice the two different listings (from 1sttoyotaparts.com) for a window relay part. What's the difference between the two? I can also buy a remanufactured motor from Advance Auto Parts for about $130 after tax. Which would you recommend? Adv. Auto also does not show the relay or regulator as an available product on their site.
In what case would I have to replace the relay or regulator? I already have to replace the motor I am certain. Thx for the help! 
What about the power locks...they are fine. But all 4 Windows are not responding to the switch controlled at the drivers side door. Any idea what that could be? It's my dad's car...I suggested fuse...but he's sure it can't be that. Besides according to him, I have no idea what I'm talking about cuz I'm " just a girl". (Except that I replaced the bevel and switch on my 2003 VW Jetta and now my windows and locks work fine!)
I would guess it's the switch, as you suggest
