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Washer Fluid Level Indicator: Description and Operation

LOW WASHER FLUID INDICATOR

The washer fluid level switch is an input to the body control module which commands the instrument panel cluster to turn the low washer fluid indicator on or off through the class 2 serial data circuit. The washer fluid level signal circuit is supplied ignition voltage through a resistor then monitored within the body control module. The washer fluid level switch is normally open so the body control module detects ignition voltage on the washer fluid level signal circuit whenever the washer fluid level is not low. When the washer fluid level reaches the point where the driver should be informed that the washer fluid is low, the washer fluid level switch closes. When the washer fluid level switch is closed the washer fluid level switch signal circuit voltage is pulled low, and the body control module commands the instrument panel cluster to illuminate the low washer fluid indicator. In order to prevent the low washer fluid indicator from flashing due to sloshing in the washer fluid container, the body control module is programed with a 30 second delay before changing states of the low washer fluid indicator during an ignition cycle.