Heating wiper support, function - GF82.30-P-2003FL

MODEL 212 

Function requirements, general 

• "Engine running" or "drive train operational" signal on
• Outside temperature T < 5 °C

The CDI control unit (N3/9) (diesel engine) or the ME-SFI [ME] control unit (N3/10) (gasoline engine) transmits the "Engine running" or "Drivetrain operational" signal via the chassis CAN (CAN E) (up to 28.02.2013) or chassis CAN 1 (CAN E1) (as of 01.03.2013) to the front SAM control unit with fuse and relay module (N10/1).

The outside temperature is detected by the outside temperature sensor (B14). The front SAM control unit reads in the data of the outside temperature sensor directly, calculates the actual outside temperature and sends this to the instrument cluster (A1) via interior CAN (CAN B). The instrument cluster calculates the outside temperature to be displayed, taking the vehicle speed and the heat dissipated from the engine into account, and sends this via interior CAN to the front SAM control unit.

If the front SAM control unit cannot receive an outside temperature value from the instrument cluster, it calculates the outside temperature itself.

Heated wiper park position, general 

Heating the wiper park positions at low outside temperatures prevents the wiper blades from freezing to the windshield.

Heated wiper park position function sequence 

The front SAM control unit switches on the wiper park position heater (R2/10) when the engine is running and at an outside temperature of T < 5 °C. This takes into consideration the engine temperature at which the wiper park position heater was switched on. If the weather is currently precipitation free, the maximum operating time is t = 25 min. If the outside temperature rises to a value of T > 15 °C, the front SAM control unit switches off the wiper park position heater. The front SAM control unit reads in all the relevant data and actuates the wiper park position heater accordingly.

The wiper park position heater is switched off automatically under the following conditions:

• No wiper request for t > 25 min. and engine coolant temperature of T < 70 °C
• Engine coolant temperature of T < 70 °C and sun sensor (B32/3) signaling "Solar radiation through the windshield". The sun sensor information is not evaluated until after t = 15 min.
• No wiper request for t > 15 min and engine coolant temperature of T > 70 °C.

  If a wiper request is then pending, the wiper park position heater is activated again.

  If the windshield has only been washed, the front SAM control unit then switches off the wiper park position heater after t = 10 min.

• When the vehicle is stationary, the wiper park position heater is switched off after t = 10 min.

The automatic air conditioning control and operating unit (N22/7) reads in the data of the sun sensor directly and transmits this via the interior CAN to the front SAM control unit. The wiper request is defined by means of the switch position of the combination switch (S4). The steering column tube module control unit (N80) reads in the switch position of the combination switch directly and sends this over the chassis CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013) to the front SAM control unit. The engine coolant temperature is recorded by the coolant temperature sensor (B11/4). The CDI control unit or the ME-SFI [ME] control unit reads in the signal of the coolant temperature sensor directly, calculates the coolant temperature and transmits it via the chassis CAN (up to 28.02.2013) or chassis CAN 1 (as of 01.03.2013) to the front SAM control unit.

	Electrical function schematic for heated wiper park position		PE82.35-P-2053-97DAA
	Overview of system components for windshield wiper system		GF82.30-P-9996FL