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.

If there is water in the windshield, it means the beam is not reflected at all. The degree of lost beam indicates the degree of the glass surface wetness.

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 the following conditions :

• Contamination of the measurement surface.
• Air bubbles between the windshield and the coupling pad contact surface.
• The movement of coupling pad by vibration.
• Damaged wiper blade.

AUTO OPERATION 

1. Operation Condition
   OPERATION CONDITION
   
   

   Operation mode	Operation condition
   Direct mode	Switch AUTO is basic operation condition that rain sensor perceives dry windshield. From this condition, the rain sensor decides the wiper operation mode depend on the quantity and time of measured rainwater
   Intermittent mode	Operation pauses between 0.5 ~ 5 seconds, then the wipers switch to intermittent mode
   Low speed	Operate continuously at low speed
   High speed	Operate continuously at high speed

2. Safety Function
   • When there is an ice in the sensing field, the rain sensor cannot recognize the correct working condition.
   NOTE: Do not operate the rain sensing wipers unless the windshield is completely clear of ice and snow.
   • Glass damage : rain sensor cannot perceive the damaged windshield within the sensing field.
   • The rain sensor will not operate properly if detached from the windshield.
   • If the wiper ECU does not transmit any effective data in 5 seconds, the rain sensor turns off LED. If the intermittent wiper signal is interrupted for >2 sec, the wipers are moved to the parking position.
   • If a rain sensor signal communication error lasts for > 5 sec, the wipers are moved into the parking position.
   • If the rain sensor transmits an error to the wiper ECU, the wiper ECU stops the AUTO function after 4.5 seconds.