GMC 2014 Yukon/Yukon XL Owner's Manual page 269

Blizzard Conditions
Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use Roadside
Assistance. See
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.
(Continued)
Driving and Operating
Warning (Continued)
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.
For more information about
carbon monoxide, see
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
(Continued)
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
9-13
.