Sunlight penetration photosensor -G107
The sunlight penetration
photosensor -G107 is located in the defroster vent cover.
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 current.
increase in current indicates a higher sunlight penetration to the air conditioner
control unit, which in turn adjusts the interior temperature: the temperature
flap and fresh air blower are operated accordingly.
control unit operates with an assumed fixed value for sunlight penetration if
the signal fails.
readout of the sunlight penetration photosensor -G107 can be changed by shining
a suitable lamp onto the sensor.
J If the
system is intact, when the sunlight penetration photosensor -G107 is covered
over the blower speed must fall.
J If a
permanent penetration of around 900 Watts per mІ (corresponding
to around 3.2V) is displayed regardless of the light shining
on the sunlight penetration photosensor -G107, check the cabling to the
photosensor according to the current flow diagram.
sunlight penetration readout is heavily dependent on the season and the time of
day, as well as on the vehicle's location (in Central Europe up to about 900
Watts per mІ is displayed at maximum sunlight penetration levels in the
J A Air conditioner;
Rep.Gr. 87; Removing and installing sunlight penetration photosensor -G107
J A Current flow