Exterior rearview mirror position measurement, function - GF88.79-P-4000S

MODEL 215, 220 (except, 220.063) 

MODEL 220.063 with CODE (275a) Memory package (driver's seat, steering column, mirrors) 

Function 

A potentiometer for measuring the position is located on each of the shafts for the vertical mirror adjustment motors (up/down) (M21/1m1)/(M21/2m1)  and horizontal mirror adjustment motors (in/out) (M21/1m2)/(M21/2m2)  in the left and right exterior mirrors.

The voltage measured at the center potentiometer cap depends on the associated mirror glass position. It is read in by the left front door control module (N69/1)/right front door control module (N69/2)  where it is evaluated for measurement of the position.