Headlamp cleaning system (HCS), function - GF82.15-P-0002GZ

MODEL 164.1 /8 up to 31.5.07 with CODE (600) Headlamp cleaning system 

Function requirements: 

• C. 15R On
• Low beam switched on

Manual actuation 

The request triggered by actuating the HCS [SRA] switch (S1s7) is read in by the upper control panel control unit (N72/1) and forwarded via the Controller Area Network bus Class B (interior) (CAN-B) to the front SAM control unit (N10). The front SAM control unit actuates the HCS [SRA] pump (M5/2) for approx. 1 s. The HCS [SRA] pump builds up pressure in the washer fluid line. The water pressure acts against the return springs in both telescopic nozzles.

The telescopic nozzles are extended, and in doing so they open the flaps in the bumper and spray washer fluid onto the headlamp lenses.

After the actuation stops, the pressure in the washer fluid line drops and the spring force acts on the telescopic nozzles moving them back into their starting position. The flaps in the bumper are closed by the spring action.

Pressing the HCS [SRA] switch again when a headlamp cleaning cycle is being performed has no effect. A further headlamp cleaning cycle can only be initiated after the previous one has ended.

Automatic actuation 

With the low beam switched on, the HCS [SRA] pump is automatically actuated by the front SAM control unit following 15 actuations of the windshield washer system (time interval between individual actuations min. 2.5 s).

For each request, the internal counter in the front SAM control unit is incremented by one until it reaches a value of "15", whereupon the HCS [SRA] pump is actuated and the counter is reset to "0".

At circuit 15 OFF or when the low beam is switched off, the internal counter is reset to "0".