A rear window washer motor is an electric device that is fitted to the external bodywork of a vehicle and used to spray water from behind the rear window. The water helps remove small particles from the surface of the glass, and can be used in conjunction with the front windshield washer fluid reservoir. A rear window washer motor typically consists of a frame which has metal arms on it; these arms are articulated at one end, so they can move up and down.
There are also small square holes in this frame, which enable arm movement; there will be either two or four holes per side depending on how many pipes there are connected to the arms on each side. The outside of the frame has an electric cable attached to it, and this cable runs to the engine compartment of the vehicle. The engine compartment contains a pump, which is powered by the engine to enable fluid to be sprayed through the arms that project from the frame. A rear window washer motor should therefore be well secured in place, so that it does not work loose and get damaged.
The rear window washer motor is usually fitted under or next to a tailgate of a car, but can also be fitted elsewhere on a vehicle such as on a pillar or even on a luggage rack if one is fitted.