1. Faulty master switch: The master switch that controls all the power windows in the vehicle may be faulty. Check if other power windows are working properly. If they are not, the master switch may need to be replaced.
2. Broken or disconnected wire: The wiring that connects the master switch to the back passenger window motor may be broken or disconnected. Check the wiring for any damage or loose connections and repair or replace as needed.
3. Faulty window motor: The window motor itself may be faulty and unable to retract the window. Check if the motor is making any noise when the switch is activated. If it is not, the motor may need to be replaced.
4. Window regulator issue: The window regulator, which is the mechanism that moves the window up and down, may be faulty or obstructed, causing the window to not retract properly. Check the regulator for any damage or obstructions and repair or replace as needed.
