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Home >> Volvo >> 2009 >> V70 >> Repair and Diagnosis >> Electrical >> Charging Systems >> Alarm, Electrical Control Modules, Brakes, Brake Control Module (BCM) - Design And Function >> Central Electronic Module (CEM) >> Design >> Sun Sensor
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Sun Sensor

Fig 1: Identifying Alarm LED
GLL153677Courtesy of VOLVO CARS CORPORATION

The sun sensor consists of a photo diode powered from the central electronic module (CEM). The conductivity of the diode depends on the amount of light to which it is exposed.

The diode is located under a diffusing lens which reduces the sensitivity of the photo diode to the angle of the light hitting it. Increased sun intensity reduces the voltage over the photodiode.

The control module measures the voltage across the photo diode and converts the voltage to information which is then transmitted to the climate control module (CCM) via the controller area network (CAN).

The sun sensor and its housing are located in the center of the dashboard at the windshield together with the twilight sensor and alarm diode.

From and including structure week 2007 46-, the sun sensor is replaced by twin sun sensors.

There are diagnostics for the sun sensor.