Automatic dimming outside mirror and inside rearview mirror, function - GF88.79-P-2010FL

MODEL 212 with CODE 249 (Automatic dimming inside rearview mirror and outside mirrors) with CODE 494 (US version) 

MODEL 212 with CODE 249 (Automatically dimming inside rearview mirror and outside mirror including fold-in outside mirrors) without CODE 494 (US version) 

Function requirements, general 

• Circuit 15R ON
• No overvoltage or undervoltage
• Reverse gear not engaged
• Interior illumination not switched on

The electronic ignition switch control unit (N73) transmits circuit 15 status to the front SAM control unit with fuse and relay module (N101) via the interior CAN (CAN B).

Automatic dimming outside mirror and inside rearview mirror, general 

The mirror glass on the inside rearview mirror (A67) and left outside mirror (M211) dims electrochromatically. This is realized by a layer of electrolyte gel in the mirror glass which controls the light permeability in increments depending on the voltage applied.

Automatically dimming outside mirror and inside rearview mirror, function sequence 

The inside rearview mirror senses the ambient light via the mirror dimming light sensor, forward (A67h1) and the light hitting the mirror glass via the mirror dimming light sensor, rearward (A67h2).

The inside rearview mirror evaluates the input factors and transmits the mirror dimming request to the front SAM control unit vi a the wiper/inside rearview mirror LIN (LIN 2).

The front SAM control unit transmits this to the left front door control unit (N69/1) via the interior CAN.

The left front door control unit receives the dimming request and supplies the corresponding actuation voltage to the mirror dimming (M21/1h1) of the outside mirror.

The mirror glass in the interior mirrors is dimmed by the interior mirror itself through activation by the mirror dimming (A67h3).

If an interior illumination is switched on during mirror dimming or the reverse gear is engaged, the dimming is interrupted.