GF68.49-P-0003R Automatically Dimming Inside Rearview Mirror, Function

GF68.49-P-0003R Automatically Dimming Inside Rearview Mirror, Function

Function requirements
^ No overvoltage/undervoltage
^ Circuit 15R or circuit 15 ON

Function
The glass of the inside rearview mirror (A67) can be electro- chromatically dimmed. The mirror glass 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 unit (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 unit (N70).

The inside rearview mirror (A67) dims between 6% and 80% and depending on the voltage applied (U=0 V up to 1.5 V).
The two input factors are sensed by the mirror dimming forward sensor (A67h1) mirror in the mirror housing (rear) and the dimming rearward sensor (A67h2) in the mirror glass of the inside rearview mirror (A67).

A CAN message is transmitted when the interior lamp is switched on via the interior CAN or via the engine compartment CAN when the reverse gear is engaged; then the inside rearview mirror (A67) rapidly is always switched to the maximum brightness. This is achieved by means of an additional signal lead from the overhead control panel control unit (N70) to the inside rearview mirror unit (A67).

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