Passenger-side window goes down but not up; what might cause this?

have you pulled the door card off? could be a lose wire on that side of the switch, it could also be that that side of the switch is fried. take a test light to it and try using the swithc both ways touch the test light to the side that goes up when trying to put it up and it should light up if voltage is present.

Plain and simple, sounds like the window motor is worn out and doesn't have the juice to get the window back up. Good luck

same problem i have with my 99 impreza. with mine its the switch i would replace it after using a test light just to be sure

2018 forester xt same problem. I roll window all the way down then up. Often it will roll back down by itself and you must repeat roll down then up. I was told dirty sensors.