Adjusting the rearview mirror dimming function
Bright light entering the vehicle from behind, e.g. from the headlights of following vehicles, could reflect in the rearview mirror and door mirrors and cause a glare. Use the dimming function when light from behind is distracting.
Auto-dim
If bright light enters the vehicle from behind, the door mirrors will automatically dim when it is dark outside or when lighting conditions are low, for example when driving in tunnels. Auto-dim is always active when the engine is running, except when reverse gear is engaged.
Note
Adjustments to the sensitivity level will not be noticeable immediately but will instead take effect after a short period of time.
Tap 
in the center display.
in the center display.Tap Controls.
Choose a setting under Mirror auto dimming.
The rearview mirror instead has two sensors - one pointing forward and one pointing rearward - which work together to identify and eliminate glare. The forward-pointing sensor monitors ambient light, while the rearward-pointing sensor monitors light from the headlights of following vehicles.
For the door mirrors to be equipped with auto-dim, the rearview mirror must also be equipped with auto-dim.
Note
If the sensors are obstructed by e.g. a parking permit, transponder, sunshade or objects on the seats or in the cargo compartment in a way that prevents light from reaching the sensors, the auto-dim function in the door and rearview mirrors will be reduced.