Sunlight penetration photosensor -G107
A ... Defroster vent screen
B ... Sunlight penetration
C ... Connector on sunlight
penetration photosensor -G107
D ... LED for central locking
and interior monitoring
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
The sunlight passes through a filter and an
optical element onto the photodiode. The filter protects the optical element against
Photodiodes are 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.
Consequently, the 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
J The control unit operates with an assumed
fixed value for sunlight penetration if the signal fails.
J The 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.
J The 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 Summer).
A Air conditioner; Rep.Gr. 87; Removing and
installing sunlight penetration photosensor -G107
A Current flow diagram; ELSA