Left front door control unit, component description - GF72.29-P-4141GZ

MODEL 164.1/8

Location

The left front door control unit is located in the upper area of the left door inside.

Fig 1: Identifying Left Front Door Control Unit

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Task

The left front door control unit is connected with the controller area network bus, class B (interior compartment) (CAN B) to exchange data and has the following purposes:

Reading in switches:

Driver power window and outside mirror adjustment switch group (S20/1)
- Rear side windows child safety lock switch (S20/1s5)
- Outside mirror fold-in/out switch S20/1s9
- Outside mirror adjustment rocker switch S20/1s12
- Open vent window switch (S20/1s15)
- Close vent window switch (S20/1s16)
Outside mirror adjustment switch S50
Open and close switch for rear-end door, driver (S15/3)
Left interior CL [ZV] switch S85/5

Reading in sensors:

Left front IR receiver (A26/1)
Left front power window motor Hall sensor (M10/3)
Mirror up/down adjustment potentiometer (M21/1r2)
Mirror in/out adjustment potentiometer (M21/1r3)

Switching loads via internal semi-conductor switches:

Left outside mirror turn signal lamp (E6/5)
Left front door entrance/exit lamp (E17/3)
Left front door inside handle illumination (E17/11)
Left front power window motor (M10/3)
Left front door CL [ZV] motor (M14/6)
Left electrically adjustable and heated outside mirror (M21/1)
Left outside mirror ambient lamp (M21/1e1)
Automatic mirror dimming (M21/1h1)
Mirror fold-in motor (M21/1m3)
Mirror heater (M21/1r1)
Illumination of driver power window and outside mirror adjustment switch group

The left front door control unit is connected with the CAN interior bus to exchange data.

The driver power window and outside mirror adjustment switch group is read in by the left front door control unit via a LIN BUS

Task in combination with air conditioning

The left front door control unit senses the window position in the left front door of the vehicle and stores this information on the CAN B.

The AAC control and operating unit (N22) or the comfort AAC control and operating unit (N22/7) reads in the signals for the "Driver door ON" window position, to achieve better control quality in the open position

Recirculated air convenience closing, task

When the air recirculation switch (N22s2 or N22/7s2) is pressed for longer than 1.5 s, the convenience closing function is activated. The left front door control unit stores the momentary window position and closes the window if it is open in the automatic mode. When the convenience closing function is completed, the window is returned to the stored position when the air recirculation switch is pressed again for longer than 1.5 s.