A rear wiper motor is a device that turns the wiper arm assembly and wiper blade on the rear window of some vehicles. The rear wiper is generally used for clearing dirt and debris off the rear window, but it is typically not used as much as a front windshield wiper motor. Over time, however, these components do fail due to an electrical short, or from the motor simply burning out. Once the motor has failed, the only thing you can really do is replace it. To do so, you're going to need to know how to change a rear wiper motor.
Disconnect the cable running to the negative terminal on the car's battery. To do this, loosen the nut on the cable clamp until the clamp is loose enough for you to slide the cable clamp off the negative battery terminal.
Pull the wiper arm away from the rear windshield until the wiper arm locks into a vertical or semi-vertical position or is perpendicular to the rear windshield.
Remove the nut holding the wiper arm assembly to the rear wiper motor.
Pull the wiper arm off the wiper motor assembly.
Unplug the rear wiper motor plug/harness.
Remove the screws holding the rear wiper motor to the inside of the vehicle at the base of the rear window.
Pull the rear wiper motor off.
Install the new wiper motor and put the wiper motor and arm assembly back on the vehicle by reversing the completed steps.