Re: Power Window Switch
I'm not familiar with the exact electrical connections or wire diagrams of the door window switches, but I have done extensive work on the interior dash and rear tailgate window switches.
The rear tailgate window key recieves its power from the interior dash swtich. Power to operate the rear key switch is only provided when the interior switch is in "neutral" position. This prevents a cross connection of both "up" and "down" signals at once. This means that a faulty interior switch could make it seem as though the tailgate key swtich is broken, when in fact it may not be.
If the door switches are anything like the tailgate & dash switches, then I bet the problem lies in your divers side door switch and not the passenger side. This would make more sense since the drivers swtich has control over both windows. If the drivers side has a poor or broken connection, then power may not be sent to the passenger side. This would also explain why your inspection of the passenger side switch seemed to be ok.
Again, I don't know much about the door window switchs, but before you go out and buy a new passenger side switch, I would seriously consider that the drivers side may be the switch at fault. Also, the drivers side switch is likely to recieve more wear and tear than the passenger side so it seems likely that it would break before the passenger side does. See if you can find a wiring diagram in a repair manual to check the connections.
Hope this helps!