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RAIN SENSOR
RODIUS 2005.07
8610-11
Rain sensor unit (including cover)
2. RAIN SENSOR OPERATION
The rain sensor is installed on the specific heat treated windshield that has minimum 13% of
transmittance rate with specified intensity of radiation. It is installed on the glass with a
adhesive of Sorepa.
It communicates with STICS and makes the wipers to operate automatically under the rain
sensing mode (multifunction switch wiper: AUTO mode).
The emitting section of the rain sensor unit emits infrared rays against the windshield and then
detects the amount of rain drops by receiving reflected rays with photodiode.
The sensing section on the windshield is located just above the center point between LED and
photodiode.
Components and functions of the rain sensor unit
Unit latch
Rain
sensor unit
PCB assembly and emitter lens
Emitter lens
The LED emits the infrared
rays is located at bottom and the lens guides the infrared rays to target point.
Receiver lens
The receiver lens guides the reflected infrared rays from windshield to photodiode.
Housing and
receiver lens
Housing and PCB
Rear Front
0-7
RAIN SENSOR
RODIUS 2005.07
8610-11
4. FUNCTIONS OF RAIN SENSOR
1) Windshield Glass and Coupler Attachment
Check the outer windshield surface of sensing area for wear, damage and scratch. The sensor
is able to compensate the wear up to a specific level. Check the coupler attached surface of
windshield for porosity. If the porosity exists, the sensor cannot function properly.
2) Recognition of AUTO Mode
3) Instant Wipe Function
When the variable resistance knob on the multifunction wiper switch is turned by each 1 stage
from low sensitivity (Smark) to high sensitivity (F mark), the wiper operates one cycle.
And, the wiper also operates during raining up to 5 minutes after rain stops.When the engine is started with the wiper switch “AUTO” position, the wiper operates
one cycle to remind a driver that the wiper switch is in “AUTO” position.
When the wiper switch is turned to “AUTO” from OFF, the wiper operates one cycle. It
always operates one cycle for the initial operation, however, the wiper does not operate
afterwards to prevent the wiper blade wear if not raining when turning the wiper switch to
“AUTO” from “OFF”. However, the wiper operates up to 5 minutes after rain stops.
If this function does not occur, check No. 2 terminal on the rain sensor. If any defective
cannot be found, check the wiper relay (LOW) for defective. 1)
2)
3)If the installed wiper brushes are out of specification (size and length), the rain sensing
area cannot be fully wiped. In this case, the rain sensor’s sensitivity could be
decreased and the wipers are not properly operated -
As described, the STICS recognizes the wiper switch “AUTO” position. If there are not
any problem, go to diagnosis mode in STICS and check the terminal that receives signal
from wiper and communication lines between rain sensor unit and STICS. -
