Windscreen Intermittent Wipe

Wiper System Networking:

Function prerequisite
Function prerequisite for all wiper system functions is:
Terminal 15R: ON
Engine hood and front doors closed

Function procedure
- The interval wiping function is switched on by turning the combination switch (S4) to position "1".
- The position of the combination switch (S4) is read in by the pushbutton control module (N73) and sent to the interior CAN as a message.
- The front SAM control module with fuse and relay module (N10/1) receives this, message and initiates a wiping procedure. (If the wipers were already in motion, this wiping procedure is completed first.)
- After a wiping procedure the wiper motor is braked.
- The interval delay starts.
- After the interval delay the wiping procedure is carried out.

Wiper motor actuation
The front SAM control module with fuse and relay module (N10/1) controls the wiper motor (M6/1) via the wiper setting 1 and 2 relay (N10/1kC) and the wiper ON/OFF relay (N10/1kH) in such a way that the wipers wipe at speed setting 1.

Interval delay interruption
If another wiper function is requested during the interval delay, this is carried out and the interval. delay is ignored. Once this function has finished, the interval delay restarts.

Interval delay in vehicles without rain sensor
Irrespective of the degree of wetting, the interval delay is approx. five seconds.

Interval delay in vehicles with rain sensor (Code 345a)
The interval delay depends on how wet the front windshield is. The front SAM control module with fuse and relay module (N10/1) analyzes the information from the rain sensor (B3B) in order to do this.

The exchange of information between the front SAM control module with fuse and relay module (N10/1) and the rain sensor (B38) takes place via the interior CAN and, since the rain sensor (B38) is not directly linked to the CAN, via the overhead control panel control module (N70) as an interface.

If the rain sensor (B38) fails the interval time is set to approx. 5 seconds.