Windshield

Operation:
The intermittent wipe function is begun by placing the combination switch (S4) in position "i", thereby connecting the input (pin A8) of the All Activity Module (AAM, N10) to terminal 15R.
This causes the AAM (pin 45) to actuate the wiper motor relay (F1k17) for up to 2 sec. The relay contact (pin a) then feeds current to the wiper motor (M6/1) at speed setting 1.
The motor continues to be supplied with power via the cam-operated switch and the normally closed contact (pin b) of relay F1k17 until the wiper arm reaches the park position. When the arm reaches the park position, the cam-operated switch operates, effectively short-circuiting the two motor connections and resulting in eddy currents which decelerate the motor.
It is here that actual intermittent wiping starts. The procedure described above is repeated for each interval.

Timing in vehicles without code 345a (without rain sensor)
After each Interval the AAM starts a new wipe cycle. Interval timing is linked to the vehicle's speed and set by the AAM at between 5 sec. when the vehicle is at rest and 1 sec. at a speed of 180 km/h.
Timing in vehicles with code 345a (with rain sensor starting 1.9.00).
With KI.15: ON, the rain sensor (B38) sets the duration of the wipe intervals.
The AAM actuates the relay wiper motor (F1k17) at the intervals set by the rain sensor (cf. Operation above). The relay is deenergized when KI. 31b is detected (wiper not in park position), or after max. 1 sec. (blockage detected).
The relay stays energized during heavy rain and the wiper functions at speed setting 1.