Front Wiper System

The Interval Wiper/Washer module allows the driver to select LO speed, HI speed, or Interval (INT) wiper operations. I INT, the interval can be spaced one second to fifteen seconds apart.

The wiper/washer lever has a momentary Washer Switch, a four-position Wiper Switch and a serrated interval time adjust ring near the end of the switch.

Washer Operation

Current flows from the RADIO fuse to energize the coil of the ACCY Relay, closing its contacts. When the Washer Switch is pressed, current from the WIPER fuse (20A) flows through the ACCY Relay to the following components: Wiper/Washer Switch, Interval Wiper Module and Washer Pump. If the Wiper Switch is in the LO or HI position, normal wiper action takes lace during washing. If the Wiper Switch is in the INT position, Interval Override operates Electronic Switch 1, which allows the Governor relay to apply power to the C terminal of the Wiper Motor. The Wipers operate in low speed. When the Washer button is released, extra wipe cycles are provided to dry the windshield. The Wipers then return to INT operation.

When the Wiper Switch is in the OFF position, the Interval Wiper Module permits operation of the wipers in LO when the Washer Switch is activated. When the washer is no longer activated, the wipers will complete one to four more cycles until the Wipe-After-Wash time has timed out. The Governor Relay is de-energized and Wiper Motor terminal C is connected to section 1 of the Wiper Motor Switch. Wiper Motor terminal L is connected to section 2 of the Wiper Motor Switch. Parking operations can now take place.

Wiper Operation

With the Ignition Switch in the ACC or RUN position, current flows through the Radio fuse to energize the coil of the ACC Relay. When LO or HI operation is selected, the Interval Wiper Module receives a ground signal through the Wiper/Washer Switch A. With the ground provided, the ACC Relay contacts will close allowing current to flow to the following components: Wiper/Washer Switch, Interval Wiper Module and Front Wiper Motor Assembly. The Interval Timer will now close Electronic Switch 1 and energize the Governor Relay. Current will now flow through the closed contacts of the Governor Relay to terminal C of the Wiper Motor. Terminal L (or H) of the Wiper Motor is grounded through Wiper/Washer Switch C. Terminal L (or H) of the Wiper Motor is grounded through Wiper/Washer Switch C. As the Wiper Motor starts to operate, Switch 1 and Switch 2 in the wiper Assembly sweep into the RUN position. When Switch 1 sweeps into the RUN position, current is applied to the Interval Wiper Module, signalling the Interval Timer to open Electronic Switch 1 and deenergize the Governor Relay. The Wiper Motor is still grounded through Wiper/Washer Switch A. The motor continues to operate in this manner until the sweep is complete and Switch 1 sweeps from the RUN to the PARKING position, the current supply to the Interval Timer is interrupted. This causes the Interval Timer to close Electronic Switch 1 and restart the operation cycle. When Electronic Switch 1 closes, a signal is sent to the Park-After-Wash Override. Each time that the signal is sent, the Park-After-Wash Override closes Electronic Switch 2 to ground and energizes the Park Override Relay in the Wiper/Washer Switch. This action prevents wiper parking during normal wiper operation.

Interval Wiper Operation

During interval operation, the wipers make single wipers at low speed separated by a variable length pause.

When first switched to INT position, the Interval Timer momentarily closes Electronic Switch 1, energizing the Governor Relay. Current flows to the Wiper Motor C terminal through the closed contacts of the Governor Relay. Ground is connected to terminal L of the Wiper Motor through switch B of the Wiper/Washer Switch.

As the Wiper Motor turns, Switch 1 of the Wiper Motor Assembly Switch changes from the grounded PARKED position to the hot RUN position. Current now flows through the R/GN sire, Switch 1 (RUN) of the Wiper Motor Switch and resets the Interval timer, which opens the electronic Switch 2. The current path continues through the normally closed Governor Relay contacts to the C terminal of the Wiper Motor, and on to ground through Switch B of the Wiper Switch. Wiping continues to the completion of one wipe. The Wipe Motor Switch returns to the PARKING position, power is removed, and the Wiper Motor stops. After a pause (controlled by the variable resistor), the Interval Timer energizes the Governor Relay to restart another wipe.

Parking Operation (Position Disconnect SUMMER Position)

When the wipers are turned OFF, the Interval Timer receives a signal through the OFF contacts of Wiper/Washer Switch A. Upon receiving this signal, the Interval Timer and Park-After-Wash Override open Electronic Switches 1 and 2, de-energizing the Governor Relay and the Park Override Relay. The motor continues to operate normally until switches 1 and 2 of the Wiper Motor Assembly sweep into the Parking Position. When the PARKING position is reached, current is applied through WIPER fuse to the Wiper Motor Assembly Switch 2, the open contacts of the Park Override Relay, and the OFF contacts of Wiper/Washer Switch B is to the L terminal of the Wiper Motor. The motor is grounded from terminal C through the open contacts of the Governor Relay and Wiper Motor Assembly Switch 1. With the polarity reversed, the Wiper Motor operates in the opposite direction and parks the wiper blades.

Parking Operation (Position Disconnect in WINTER Position)

With the Position Disconnect switched from SUMMER or WINTER, Wiper Motor operation stops as soon as Wiper Motor assembly switches 1 and 2 reach the PARKING position. This action prevents the motor from reversing direction and parking the wiper blades into their recessed positions during periods of cold weather and icing.

Standard Wiper System

The standard wiper system is basically the same as the interval wiper system. However, it does not utilize the Interval Override and Wipe-After-Wash Timer of the Interval Governor or the Interval Time Adjust of the Windshield Wiper Switch.