RAIN SENSOR CONSTRUCTION/OPERATION


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Warning
•  If vehicle servicing such as car washing is performed with the ignition switch turned to the ON position, and the wiper and washer switch is in the AUTO position, the windshield wipers may operate automatically. Always turn the ignition switch, and the wiper and washer switch off before performing servicing such as the car washing; otherwise a pinched hand or fingers could result in injury or a wiper system malfunction.
Caution
•  In the following cases, the auto light sensor cannot detect the illumination level correctly which could cause an auto light malfunction:
―  A sticker or label is adhered to the windshield above the auto light sensor.
―  The windshield is dirty above the auto light sensor.
•  Installed on the underside of the rearview mirror (windshield center).
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Rain sensor
2
Lens sensor


Operation With No Rainfall Contacting Windshield

1.  Infrared light is emitted from the LED in the rain sensor towards the windshield.

2.  The emitted infrared light passes through the lens sensor and is reflected off the windshield.

3.  The infrared light reflected off the window is received by the photodiode in the lens sensor.

4.  The photodiode receives the light, the microcomputer in the rain sensor calculates the rainfall amount from the reflection rate, converts this to an electric signal and sends a windshield wiper control signal to the PJB.

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1
Rain sensor
2
Photodiode
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Lens sensor
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Infrared light
5
Windshield
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Emitted light
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Received light


Operation With Rainfall Contacting Windshield

1.  Infrared light is emitted from the LED in the rain sensor towards the windshield.

2.  The emitted infrared light passes through the lens sensor, is received by the windshield and diffused by the rainfall contacting the windshield.

3.  The infrared light that is not diffused is reflected by the windshield and received by the photodiode in the lens sensor.

4.  The photodiode receives the light, the microcomputer in the rain sensor calculates the rainfall amount from the reflection rate, converts this to an electric signal and sends a windshield wiper control signal to the PJB.

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1
Rain sensor
2
Photodiode
3
Lens sensor
4
Infrared light
5
Windshield
6
Emitted light
7
Received light
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Rainfall
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Diffusion