Wiper/Washer Systems: Operation
The basic washer pump is a spring loaded piston enclosed in a plastic cylinder housing with an actuator plate extending from the cylinder housing. A valve assembly, consisting of two exhaust and one intake check valve, is attached to the end of the cylinder housing. A tang on the piston actuator plate holds the plate in a lock-out position, (no pumping action). To start the pump, push washer button which will energize the relay. This pulls the relay armature toward the coil allowing the ratchet gear pawl to engage the ratchet gear and begin rotation. This sequence starts pumping action.