GMC 2012 Sierra Denali Owner's Manual page 264

9-14 Driving and Operating
Blizzard Conditions
Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use the Roadside
Assistance Program (U.S. and
Canada) on page 13 8 or Roadside
Assistance Program (Mexico) on
page 13 10. To get help and keep
everyone in the vehicle safe:
Turn on the hazard warning
flashers.
Tie a red cloth to an outside
mirror.
WARNING
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
WARNING (Continued)
If the vehicle is stuck in the snow:
Clear away snow from around
the base of your vehicle,
especially any that is blocking
the exhaust pipe.
Check again from time to
time to be sure snow does
not collect there.
Open a window about 5 cm
(2 in) on the side of the
vehicle that is away from the
wind to bring in fresh air.
Fully open the air outlets on
or under the instrument
panel.
Adjust the climate control
system to a setting that
circulates the air inside the
vehicle and set the fan speed
to the highest setting. See
Climate Control Systems in
the Index.
(Continued)
WARNING (Continued)
For more information about
carbon monoxide, see Engine
Exhaust on page 9 33.
Run the engine for short periods
only as needed to keep warm, but
be careful.
To save fuel, run the engine for only
short periods as needed to warm
the vehicle and then shut the engine
off and close the window most of
the way to save heat. Repeat this
until help arrives but only when you
feel really uncomfortable from the
cold. Moving about to keep warm
also helps.
If it takes some time for help to
arrive, now and then when you run
the engine, push the accelerator
pedal slightly so the engine runs
faster than the idle speed. This
keeps the battery charged to restart
the vehicle and to signal for help
(Continued) with the headlamps. Do this as little
as possible to save fuel.