Wiper and Washer Systems: Description and Operation

Low-speed and high-speed wiper operation
- When the ignition switch is in the ACC or ON position and the wiper switch is turned to the LO or HI position a switch "on" signal is sent to the instrument panel ECU which sends a signal to the assist-ECU via the SWS communication line.
In response to this signal, the assist-ECU operates the wipers at a low speed or high speed according to the signal received.

Auto wiper stop operation
- When the wiper switch is turned to OFF, the cam contacts in wiper motor allow current to flow through the auto wiper stop circuit, allowing the wipers to operate to the stop position.

Intermittent wiper operation
- When the ignition switch is in the ON or ACC position and the wiper switch is turned to the Auto position, a switch "on" signal is sent to the instrument panel ECU. The instrument panel ECU determines wiper sweep cycle timing according to the position of the variable intermittent control switch and vehicle speed and sends a signal to the Assist-ECU via the SWS communication line.
The assist-ECU operates the wipers according to the signal received.

Washer-wiper operation
- When the washer switch is operated with the ignition switch in the ACC or ON position, a signal is sent to the instrument panel ECU which signals the assist-ECU to operate the washer motor.