Rain / Driving Light Sensor

Rain / Driving Light Sensor

The rain-driving light sensor has integrated sensors that sense the wetness on the windshield glass and the ambient light.

Driving light sensor
The driving light sensor consists of two photodiodes and an electronic evaluation unit. The photodiodes are arranged in such a way that both light striking the sensor from the front and light striking the sensor from above (ambient light) are sensed.

Requirements for fault-free operation of the driving light sensor are those of the rain sensor.

If there is a change in the lighting conditions, a signal is issued across the data bus K-CAN. When the Automatic Light Control is active, the light module switches the low-beam headlight on or off.

The light sensing is active as of terminal R, independent of whether the automatic driving light control system is switched on or off.

After replacement, the driving light sensor must be encoded via the vehicle order and is thus adapted to the windscreen.

Coding the rain / driving light sensor
Coding of the rain / driving light sensor is required:
- After replacing the windshield
- After replacement of a rain / driving light sensor

At each new start, the junction box electronics (JBE) check whether the coding data stored in the rain / driving light sensor match the coding data stored in the junction box electronics.

In the event of deviations, the junction box electronics run automatic coding of the rain / driving light sensor in accordance with the target coding data.

The automatic driving lights control provides a coding possibility to change the sensitivity settings (Japanese version: changed sensitivity settings).

Restrictions due to factors inherent in the system

Light sensor:
Due to the high surrounding brightness, fog cannot be detected by the light sensor.
The light sensor is sensitive to light in the infrared range. The infrared proportion is high if there is dense cloud cover. With lighter cloud cover or blue sky - above all in winter - the sensor receives considerably fewer infrared light proportions. This means the light sensor switches the light on earlier or leaves it on for longer. In well illuminated tunnel entrances, start-up can be delayed. The high level of illumination means that the measured values are above the switch-on threshold.

The formation of bubbles on the bonding surface of the optical element impairs the light function
No liability can be accepted for printing or other faults. Subject to changes of a technical nature