Wiper Operation

The wiper switch is controlled by a lever built into the combination switch. There are three wiper switch positions:
^ LO speed
^ HI speed
^ INT (Intermittent - with intermittent wiper models) With the ignition switch in the ACC or ON position power is supplied
^ through 20 A fuse (No. (7), located in the fuse block)
^ to wiper motor terminal (4).

Low and high speed wiper operation
Ground is supplied to wiper switch terminal (6) through body grounds (M49), (M105) and (M42).
When the wiper switch is placed in the LO position, ground is supplied
^ through terminal (4) of the wiper switch
^ to wiper motor terminal (2)
With power and ground supplied, the wiper motor operates at low speed.
When the wiper switch is placed in the HI position, ground is supplied
^ through terminal (3) of the wiper switch
^ to wiper motor terminal (3)
With power and ground supplied the wiper motor operates at high speed.

Auto stop operation
With wiper switch turned OFF, wiper motor will continue to operate until wiper arms reach windshield base. When wiper arms are not located at base of windshield with wiper switch OFF, ground is provided
^ from terminal (4) of the wiper switch
^ to wiper motor terminal (2), in order to continue wiper motor operation at low speed.
The ground path to terminal (4) of the wiper switch is supplied
^ through terminal (8) of the wiper switch
^ to wiper amplifier shorting connector terminal 3 (without intermittent wipers), or
^ to wiper amplifier terminal 3 (with intermittent wipers)
^ through wiper amplifier shorting connector terminal 6 (without intermittent wipers), or
^ through wiper amplifier terminal 6 (with intermittent wipers)
^ to wiper motor terminal 5
^ through terminal 6 of the wiper motor, and
^ through body grounds M49, M105 and M160.
The ground path is interrupted and the wiper motor stops when the wiper arms reach the base of the windshield.

Intermittent operation
The wiper motor operates the wiper arms one time at low speed at a set interval of approximately 4 to 12 seconds. This feature is controlled by the wiper amplifier.
When the wiper switch is placed in the INT position, ground is supplied:
^ to wiper amplifier terminal (4)
^ from wiper switch terminal (7)
^ through wiper switch terminal (6), and
^ through body grounds (M49), (M105) and (M160).
The desired interval time is input:
^ to wiper amplifier terminal (5)
^ from wiper switch terminal (1).
Based on these two inputs, an intermittent ground is supplied:
^ to wiper motor terminal (2)
^ through the wiper switch terminal (4)
^ to wiper switch terminal (8)
^ from wiper amplifier terminal (3).
With power and ground supplied, the wiper motor is activated.
The wiper motor operates at low speed at the desired time interval.