Automatic dimming inside rearview mirror, function - GF68.49-P-0003T

MODEL 211.0/2/6 with CODE (249b) Automatic dimming interior rearview mirror and outside mirror (driver) 

Function prerequisites 

• No overvoltage or undervoltage
• Circuit 15R or 15 ON

Function 

The mirror lens of the inside rearview mirror (A67) can be electro-chromatically dimmed. The mirror lens between the reflector and the glass cover contains a layer of electrolyte gel. The light transmission ratio of this gel changes when a voltage is applied to it.

The inside rearview mirror (A67) relates the light shining in from the rear in proportion to the ambient light, calculates the necessary degree of dimming, darkens the mirror surface and supplies the dimming information to the overhead control panel control module (N70).

The inside rearview mirror (A67) dims the mirror between 6 % and 80 % in line with the voltage applied (U=0 V up to 1.5 V). The two input parameters are detected by the automatic mirror dimming forward sensor (A67h1) in the mirror housing (rear) and by the automatic mirror dimming backward sensor (A67h2) in the mirror lens of the inside rearview mirror (A67).

A CAN message is transmitted if an interior lamp is switched on via passenger compartment CAN bus or the reverse gear is engaged via the CAN engine compartment. The inside rearview mirror (A67) then always changes quickly to maximum brightness. This is achieved by means of an additional signal lead from the overhead control panel control module (N70) to the inside rearview mirror (A67).

The inside rearview mirror (A67) is the master for the outside mirror dimming (driver side).