Each power window in a vehicle has its own motor located inside the door panel. The motor’s purpose is to roll the window up and down along the window track. If it is not functioning properly, the window may not roll up, down, or both.
The power window motor and its gear are generally a sealed unit, that does not require regular maintenance. However, like anything else, it is susceptible to wear down over time or fail suddenly. If this happens, the motor will need to be replaced.