Wiper and Washer Systems: Description and Operation

WINDSHIELD WIPERS AND WASHERS

Windshield Low-speed (and High-speed) Wiper Operation
If the windshield low-speed wiper switch is turned to ON position with the ignition switch at the "ACC" or "ON" position, the column switch sends a low-speed wiper ON and high-speed wiper OFF signals to the front-ECU. This turns the wiper signal on and the wiper speed switching relay off (low-speed), causing the wipers to operate at low-speed.

If the windshield high-speed wiper switch is turned to the ON position, the column switch sends a low-speed wiper OFF and high-speed Wiper ON signals to the front-ECU. This turns both the wiper signal and the wiper speed switching relay on (high-speed), causing the Wipers to operate at high-speed.

Windshield Intermittent Wiper Operation
The ETACS-ECU calculates the wiper operation interval according to the voltage signal sent from the column switch and vehicle speed. Then the ETACS-ECU sends a signal to the front-ECU. The front-ECU determines the wiper operation interval and turns on the wiper relay signal relay. This causes the wiper auto stop relay to turn on. Then the wiper auto stop relay will turn off after the wipers reach the park position. This causes the wiper signal relay and then the wipers to turn off. If the wiper signal relay remains off for the wiper operation interval, the relay turns on again,causing the wipers to operate in intermittent mode.

Windshield Mist Wiper Operation
If the windshield mist wiper switch is turned to the ON position with the ignition switch at the "ACC" or "ON" position, the mist wiper high-speed operation signal is sent to the front-ECU. This signal turns on the wiper speed switching relay, causing the wipers to work at high-speed while the mist switch is on.

While the windshield mist wiper switch remains turned on when the intermittent mode is still working, the wipers work as the mist Wiper. However, the wipers return to the intermittent mode again when the switch is changed back to "INT."

Windshield Washer Operation
If the windshield washer switch is turned to ON position with the ignition switch at "ACC" or "ON" position, the windshield washer ON signal is sent to the front-ECU, causing the windshield wiper signal to turn on after 0.15 seconds. After the windshield washer switch signal turns off, the windshield wiper signal turns off in three seconds.

If the windshield wiper switch is turned to the ON position while the windshield wiper is at intermittent mode, the windshield washer Works for that period when the windshield washer switch remains on. Then the wipers return to the intermittent mode.

Low Washer Fluid Level Warning Light
If Ignition switch and washer fluid level switch remains "ON" (the latter alarms for washer fluid level getting low) for 2 seconds or more, ETACS-ECU illuminates low washer fluid level warning light. Even if washer fluid level switch is set to the position "OFF," ETACS-ECU illuminate low washer fluid level warning light for the following 2 seconds.