For 1990-2009 cars

### Wiper Operation

When the wiper switch is in LOW, the following action occurs:

• | Battery voltage applies to the park switch through CKT 96 and to the park switch contacts thorough CKT 91.

• | When the wiper switch is in LOW, the park switch closes its contacts, which supplies battery voltage to the wiper motor through CKT 196 and the wiper motor operates at low speed.

When you move the wiper switch to the OFF position, the park switch de-energizes, causing the mechanism to shift the wipers toward the depressed-park position. When the mechanism is in the depressed-park position, the park switch opens the wiper motor circuit, stopping the wipers.

With the wiper switch in HIGH, the following action occurs:

• | Battery voltage applies directly to the wiper motor at terminal A without passing through the park switch contacts. Terminal A is connected to a separate wiper motor brush for high speed operation.

• | The park switch coil remains energized in the HIGH position because of the voltage present at the low speed wiper motor brush when volage is applied to the high speed brush.

• | The current path from the low speed brush to the park switch coil is completed through the wiper/washer switch assembly.

A circuit breaker protects the wiper motor. The circuit breaker opens if something blocks the wipers (such as ice on the windshield, for example). The circuit breaker resets automatically after cooling.

### Washer Operation

The washer pump is energized whenever you activate the washer switch and runs as along as the switch is closed. Battery voltage is applied through the washer switch and CKT 94 to the washer pump.

Activating the washer switch also moves the wiper switch to the LOW position in order to start the wipers. The wipers must be turned off manually after the wash cycle.

### Mist Operation

When you move the wiper switch to MIST and then release the wiper switch, the wipers make one sweep at low speed and return to the park position. The circuit operation is the same as that of the LOW position.

### Pulse System

In addition to the features of a standard (non-pulse) wiper system (low and high speeds), the pulse-type windshield wiper/washer system includes an operating mode in which the wipers make single sweeps with an adjustable time interval between sweeps. The time interval is controlled by a solid-state timer in the wiper motor cover assembly. The duration of the delay interval is determined by the delay rheostat in the wiper/washer switch assembly.

A circuit breaker protects the wiper motor. If something blocks the wipers (such as snow or ice, for example), the circuit breaker opens the circuit. The circuit breaker resets automatically after cooling.

### Wiper Operation

With the wiper switch in DELAY (pulse), the following action occurs:

• | Battery voltage is applied to the wiper motor terminal B of connector C1 through CKT 91. Voltage also is applied to terminal F through CKT 94 and the pulse delay resistance in the wiper/washer switch assembly.

• | The battery voltage at terminal B energizes the park switch coil, which closes its contacts.

• | In response to the voltage at terminal F, the solid-state timer momentarily closes contact A, which applies battery voltage at terminal B to the contacts of the park switch, causing the wiper motor to start.

• | A cam operates a contact in the wiper motor cover assembly, which causes contact A to open when the wipers have completed sweeping.

• | Since the park switch coil remains energized, the wipers do not park but remain just above the park position until contact A closes again in order to start another sweep.

• | The length of delay time between sweeps is controlled by the variable-pulse delay resistor. The delay is adjustable from 0-25 seconds.

• | With the wiper switch in LOW, battery voltage is applied at wiper motor connector C1 terminals B and C through CKT 91 and CKT 97.

• | The park switch coil energizes again and battery voltage is applied to the park switch contacts and the wiper motor, which runs continuously.

• | With the wiper switch in the HIGH position, battery voltage is applied directly to the wiper motor at terminal A without passing through the park switch contacts. Terminal A is connected to a separate wiper motor brush for high speed operation.

• | Voltage is also applied through the low speed wiper motor brush to the park switch contacts and timer contact A to the park switch coil.

• | The park switch coil remains energized in the HIGH position.

• | The current path from the low speed brush to the park switch coil is completed through the wiper/washer switch assembly. An open in the circuit causes the wipers to cycle in and out of the park position in HIGH and possibly prevents low speed operation.

### Washer Operation

When you activate the washer switch, the following action occurs:

• | Battery voltage is applied to the wiper motor cover assembly through CKT 94 and CKT 97.

• | The battery voltage at terminal B of connector C1 energizes the park switch coil.

• | The cover assembly circuitry turns on the washer pump and wiper motor by closing contacts A and B.

• | The cover assembly circuitry turns the wiper motor off approximately 6 seconds after it interrupts power to the washer pump. If the wipers were in DELAY, LOW, or HIGH, the wipers return to that operation after the wash cycle.

### Mist Operation

When you move the wiper switch to MIST and then release the switch, the wipers make one sweep at low speed and return to the park position. The circuit operation is the same as that of the LOW position.