Automatic Dimming Mirror; Blind Spot Mirrors - GMC Sierra 2018 Owner's Manual

48 Keys, Doors, and Windows
See Rear Window Defogger under
Dual Automatic Climate Control
System 0 219.
Automatic Dimming
Mirror
If equipped, the driver outside mirror
automatically adjusts for the glare of
the headlamps from behind. This
feature comes on when the vehicle
is started.

Blind Spot Mirrors

If equipped, there is a small convex
mirror built into the upper and outer
corner of the driver outside mirror.
It can show objects that may be in
the vehicle's blind zone.
Driving with the Blind Spot
Mirror
Actual Mirror View
1. When the approaching vehicle
is a long distance away, the
image in the main mirror is
small and near the inboard
edge of the mirror.
2. As the vehicle gets closer, the
image in the main mirror gets
larger and moves outboard.
3. As the vehicle enters the blind
zone, the image transitions
from the main mirror to the
blind spot mirror.
4. When the vehicle is in the blind
zone, the image only appears
in the blind spot mirror.
Using the Outside Mirror with
the Blind Spot Mirror
1. Set the main mirror so that the
side of the vehicle can just be
seen and the blind spot mirror
has an unobstructed view.
2. When checking for traffic or
before changing a lane, look at
the main driver/passenger side
mirror to observe traffic in the
adjacent lane, behind your
vehicle. Check the blind spot
mirror for a vehicle in the blind