What do I need to do to fix it? I can’t figure out how to remove the trim panel to investigate it.
It sounds like the cable drum for the motor/window regulator is stripped out.
To remove the door panel:
Using a *trim stick, pry off the courtesy light from door panel and unplug/remove it.
If equipped, remove door assist handle/door cup pull.
Remove screw cover from switch panel. remove screws from switch panel and remove switch panel.
If equipped, with *trim stick, remove seat/mirror switch.
Remove screw securing door trim to door panel behind door handle.
Disconnect the clips that secure the bottom and side of the panel to the door by pulling the panel away from the door.
Tilt the top of the panel away from the door to gain access to the door handle latch rod.
Disengage the clip that secures the rod to the door handle.
Seperate the rod from the door handle.
Remove the door panel.
*Trim Stick: A flat bladed plastic tool used to remove panels/bezels from interior components without causing damage.