LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2009 >> E350 Base >> Repair and Diagnosis >> Body & Frame >> Mirrors >> Detachable Body Components -- E350 (211.256) >> Basic Knowledge >> Heat left/right exterior rearview mirrors, function - GF88.79-P-2000T

Heat left/right exterior rearview mirrors, function - GF88.79-P-2000T

Model 211.0/2 

Fig 1: Heat Left/Right Exterior Rearview Mirrors Function Diagram
G07285935Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The mirror heaters (M21/1r1 and M21/2r1) each consist of one heating resistor located on a foil on the rear of the mirror lens.

Function prerequisites 

Function 

The outside temperature is measured by the outside temperature indicator temperature sensor (14) and forwarded to the driver's side SAM control module with fuse and relay module (N10/1).

The latter relays this information to the CAN, class B bus. The front left door control module (N69/1) and right (N69/2) evaluates the information and switch the mirror heaters (M21/1r1 and M21/2r1) ON or OFF accordingly.

IMPORTANT In addition to the outside temperature, the humidity (dew point) is also used for control.

If the outside temperature value received is implausible, the mirror heater is always switched on. If the dew point value is not available, the switch-on value is set to 13°C.

Left front door control module, location/purpose GF72.29-P-4115T
Right door control module, location/purpose GF72.29-P-4116T
Driver's side SAM control module with fuse and relay module, location/purpose/design GF54.21-P-4109T