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GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-14632286) - 2021 - CRC - 11/19/20
38
Keys, Doors, and Windows
Manual Rearview Mirror
If equipped, push the tab forward for
daytime use and pull it rearward for
nighttime use to avoid glare from the
headlamps from behind.
Automatic Dimming Rearview
Mirror
If equipped, the mirror will automatically
reduce the glare of the headlamps from
behind. The dimming feature comes on each
time the vehicle is started.
Rear Camera Mirror
If equipped, this automatic dimming mirror
provides a wide angle camera view of the
area behind the vehicle.
Pull the tab to turn on the display. Push the
tab to turn it off. When off the mirror is
automatic dimming. Adjust the mirror for a
clear view of the area behind the vehicle
while the display is off.
Press
V
to scroll through the adjustment
options.
Press
t
and
u
to adjust the settings using
the indicators on the mirror. The indicators
will remain visible for five seconds after the
last button activation, and the settings will
remain saved.