Sunlight penetration photosensor -G107
A - Sunlight penetration photosensor
B - Warning lamp for SAFE function of
central locking -K133
The sunlight penetration
photosensor -G107 is located in the windscreen defroster vent.
The air conditioner
temperature control is influenced with the aid of photosensors which record the
direct sunlight penetration.
The sunlight passes
through a filter and an optical element onto the photodiode. The filter
protects the optical element against UV radiation.
light-sensitive semiconductor elements. With no light incursion only a small
amount of current can flow through the diode. When light is penetrating the
current flow increases. Thus, the stronger the light incursion the higher the
Climatronic control unit -J255 is able to deduce a higher sunlight penetration
from the increase in current and adjust the interior temperature - the temperature flap and
fresh air blower are operated accordingly.
Measured value block 025
Display zones 1 ... 4: Measured
value of sunlight penetration photo sensor† -G107-
Display zone 1: Measured
value for left side in V (Volts)
Display zone 2: Measured
value for left side in W / m2 (Watts per m2)
Display zone 3: Measured
value for right side in V (Volts)
Display zone 4: Measured
value for right side in W / m2 (Watts per m2)
There are different
versions of the sunlight penetration photosensor -G107. So be sure to use the
correct one. If a sunlight penetration photosensor -G107 not intended for this
vehicle is fitted (it delivers a different signal than configured in the Climatronic
control unit -J255), the Climatronic control unit
-J255 will not be able to evaluate the signal from the sunlight penetration photosensor -G107 and the air
conditioner control will be faulty.
conditioner; Rep.Gr. 87; Removing and installing sunlight penetration
A Current flow