Rain Sensor Functionality

The rain/light sensor contains transmitter and receiver diodes, which transmit and receive infrared light, which is directed onto the windscreen via an optical unit. The light is directed at an angle so that the light is reflected 100% on the outside surface of the screen and is transmitted back into the optical unit. To receive a 100% reflection, the outer screen surface must be clean and dry.

The rain/light sensor is active when the wiper column control switch is in the intermittent position. The rain/light sensor suspends wiper operation when the area of the windscreen for the rain/light sensor is dry and operates the wipers continuously when the windscreen is subject to heavy rainfall.

The sensitivity of the rain/light sensor can be adjusted by the driver using the intermittent rotary switch on the wiper stalk. Six sensitivity levels of the sensor can be selected, which has the effect of increasing or decreasing the wiper delay period, allow driver adjustment for the prevailing conditions. When several continuous wipe cycles have taken place, the sensor will maintain the continuous operation to avoid switching back to intermittent from a continuous wipe and back again.

The rain/light sensor receives vehicle speed information from the ABS (anti-lock brake system) module on the LIN (local interconnect network) bus via the CJB. The speed information is used only for automatic headlamp operation.

AUTOMATIC HEADLAMP OPERATION

A light sensor is incorporated in the housing of the rain/light sensor to control the operation of the automatic headlamps.

The automatic headlamps will function when the lighting control switch is in the 'AUTO' position and the CJB receives a lights on signal from the rain/light sensor.

For additional information, refer to: Exterior Lighting