My front driver side power window will roll down but wont roll back up on my 1993 4Runner.
Most likely the window switch, the switch just reverses polarity to make the window go and down, the wires that are positive and negative going down become negative and positive goin up.
Even more likely is a broken wire in the bundle going between the the door and the frame in the door hinge area. Pry back the rubber boot, check for a broken wire. (It will look something like in this photo)
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