Passenger side window woes

But... I don't think your problem is motor related. Usually, when the motor is dying, it will go down but not up. Or it will die 100%.
Since this is intermittent, it could be one of your window switches. The next time it happens, check and see what the behavior is of both window switches. (The passenger side switch is wired through the driver's side switch. So, if one is going bad, sometimes the other will work - but not always.) If one switch works and the other doesn't its easy to find the fix. If both don't work, you'll need to do some electrical tracing.

But... I don't think your problem is motor related. Usually, when the motor is dying, it will go down but not up. Or it will die 100%.
Since this is intermittent, it could be one of your window switches. The next time it happens, check and see what the behavior is of both window switches. (The passenger side switch is wired through the driver's side switch. So, if one is going bad, sometimes the other will work - but not always.) If one switch works and the other doesn't its easy to find the fix. If both don't work, you'll need to do some electrical tracing.
If you have the ability to, put a meter on it and meter out the voltage going to the motors. You'll find the drivers side is getting around 10v and the passenger side is getting around 7.5v. It's doing this because the stock wiring is not big enough to carry the full 12v the motor needs. Since the motor is trying to pull 12v some a wire that can't carry it, it overheats. Years of the motors doing this is what kills them.
The only proper fix for this, I've found, is the Auto-Trix fix. I built a kit myself using 12AWG wire and haven't had a problem since. It's not cheap, but it works and gives the motors the full 12v they need directly from the battery instead of the cars stock wiring. I highly doubt your switches are the problem.



