Kia Rio: Rain Sensor System Function

Basic Principle

Emitted Beam from luminosity diode is reflected entirely against the windshield exterior, and then turn into photo diode.

If there is water on the windshield exterior, beam separates optically, and the degree of remained beam is measured in the photo diode.

What there is water in the windshield, it means beam is not reflected all, so the degree of lost beam indicates the degree of glass surface wet.

Operation Control

Wiper ECU transmits the signal as a rain sensor, and then the rain sensor perceives the rainwater to transmit to the wiping order wiper ECU, wiper ECU controls the wiper motor according to the signal.

Contact Influence

The rain sensor can malfunction due to following condition

Operation Condition

In case that engine starts under wiper switch AUTO, rain sensor activates after once wiper operation to inform the driver that the system is under AUTO.

Rain Sensor Description

The Rain sensing windshield wiper system is a wiper system that, in addition to providing normal wiper functions off, mist, manual low speed, manual high speed, and wash, provides automatic c ...

Rain Sensor Inspection

Rain Sensing Wiper 1. In IGN2 ON state, if auto switch input (LIN communication) is ON then both wiper low relay and wiper high relay outputs are controlled by the ...

See also:

ESC OFF Switch Inspection
1. Turn ignition switch OFF and disconnect the negative (-) battery cable. 2. Remove the crash pad lower panel. (Refer to the Body ...

Front Door Adjustment
Glass Adjustment    • Check the glass run channel for damage or deterioration, and re ...

Wiper blades
Blade inspection Commercial hot waxes applied by automatic car washes have been known to make the windshield difficult to clean. Contamination of either the windshield or the wiper blades with f ...