The lens heating serves to melt ice and snow deposits. This ensures the correct operation of Active Cruise Control even in winter conditions. The heating coil is integrated in the plastic lens assembly of the ACC sensor.
The lens heating is activated by the ACC sensor through direct connection of the vehicle's electrical system voltage.
The lens heating is switched on and off as a function of the outside temperature. In addition, the engine speed must be greater than the idle speed. The upper switch-on temperature is 5°C. The lower switch-off temperature is - 5°C. A hysteresis of 2°C is taken into account in both cases.
The lens heating is deactivated at temperatures in the ACC sensor of over 50°C and at voltages higher than 16 V. In these cases, no fault is entered in the fault memory.
The heating coil is monitored for open and short-circuits. When the monitoring facility responds, a fault is entered in the fault memory and the system is deactivated.