Q: Electrical issue with window

I'm diagnosing electrical problem on my truck for my passenger window not going down it's stuck in the up position. On the driver side where all the power window switch controls all windows work beside the passenger window it won't go down . So I started to diagnosis the passenger electrical switch system . Now there is power going to the switch and to the motor but the circuit tester only shows power going to the motor when the window power switch is being activated going in the up position but activating the power switch into the down position I get no power . So do I replace the window motor or the switch ?

My car has 114000 miles.
My car has an automatic transmission.