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Wiper Relay: Description and Operation

Wiper Relays
The two Wiper Relays work in conjunction with each other to provide power to the wiper motor for Slow or Fast operation.

Both Relays are powered (Relay Term 86) by fuse F09. The On/Off Relay, a 4 pin relay receives its energizing ground (Term 85) from the BC1. The Fast/Slow Relay, a 6 pin relay, also receives its energizing ground (Term85) from the BC1. While the On/Off relay functions as a standard on/off type relay, the Fast/Slow relay operates as a switch over type relay. The at rest state of the On/Off relay is off (no power flowing through the points) and the rest state of the Fast/Slow relay is on(power flowing through one of the point sets to the slow connection of the wiper Motor).

The energized state of the On/Off relay provides power to the fast/slow relay so that while the fast/slow relay is not energized B+ flows to the slow speed connection on the wiper motor. When the Fast/Slow relay is energized by the BC1, the points are switched over to supply B+ to the Fast speed connection on the wiper motor.


On/Off and Fast/Slow wiper relays for the front wipers.