It could be the switch or the motor.
We've seen some of these where the motor works fine going down (gravity is a wonderful thing), but the motor has a problem powering the window to go up. You will need to determine if you have power giong out of the switch.
You should have power to the dark blue wire (PIN E) with the switch in the up position. If you do, the problem is the motor.
Let us know what you find.