2018 GMC YUKON XL stop start

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Climate Controls 181Front Climate Controls Automatic Operation
The system automatically controls
the fan speed, air delivery, air
conditioning, and recirculation in
order to heat or cool the vehicle to
the desired temperature.
When AUTO is lit, all four functions
operate automatically. Each function
can also be manually set and the
setting is displayed. Functions not
manually set will continue to be
automatically controlled, even if the
AUTO indicator is not lit.
To place the system in
automatic mode:
1. Press AUTO.
2. Set the driver and passenger
temperature.
To find your comfort setting,
start with 22 °C (72 °F) and
allow the system time to
stabilize. Then adjust the
temperature as needed for best
comfort. To improve fuel efficiency and to
cool the vehicle faster, recirculation
may be automatically selected in
warm weather.
The recirculation light will not come
on when automatically controlled.
Press
@ to manually select
recirculation; press it again to select
outside air.
Do not cover the solar sensor on the
top of the instrument panel near the
windshield. This sensor regulates
air temperature based on sun load.
See “ Sensors ” later in this section.
Manual Operation
O : Press to turn the climate control
system on or off. When off is
selected, the system will stop air
from flowing into the cabin. If on is
selected, a button is pressed, or a
knob is turned, the climate control
system will turn on and operate at
the current setting.
9 : Turn clockwise or
counterclockwise to increase or
decrease the fan speed. Press
AUTO to return to automatic
operation. The maximum auto fan speed can
be adjusted. See “ Climate and Air
Quality ” under Vehicle
Personalization 0 158 .
Driver and Passenger
Temperature Control : The
temperature can be adjusted
separately for the driver and
passenger.
Turn the knob clockwise or
counterclockwise to increase or
decrease the driver or passenger
temperature setting.
SYNC : Press to link the passenger
and rear climate temperature
settings to the driver setting. The
SYNC indicator light will turn on.
When the passenger or rear climate
settings are adjusted, the SYNC
indicator light turns off.
Air Delivery Mode Control : Press
Y ,
\ ,
[ , or
- to change the
direction of the airflow. An indicator
light comes on in the selected mode
button.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
192 Driving and Operating 3. Turn the steering wheel to go
straight down the roadway.
Loss of Control Skidding There are three types of skids that
correspond to the vehicle's three
control systems:
.
Braking Skid — wheels are not
rolling.
.
Steering or Cornering Skid —
too much speed or steering in a
curve causes tires to slip and
lose cornering force.
.
Acceleration Skid — too much
throttle causes the driving
wheels to spin.
Defensive drivers avoid most skids
by taking reasonable care suited to
existing conditions, and by not
overdriving those conditions. But
skids are always possible.
If the vehicle starts to slide, follow
these suggestions:
.
Ease your foot off the
accelerator pedal and steer the
way you want the vehicle to go. The vehicle may straighten out.
Be ready for a second skid if it
occurs.
.
Slow down and adjust your
driving according to weather
conditions. Stopping distance
can be longer and vehicle
control can be affected when
traction is reduced by water,
snow, ice, gravel, or other
material on the road. Learn to
recognize warning clues — such
as enough water, ice, or packed
snow on the road to make a
mirrored surface — and slow
down when you have any doubt.
.
Try to avoid sudden steering,
acceleration, or braking,
including reducing vehicle speed
by shifting to a lower gear. Any
sudden changes could cause
the tires to slide.
Remember: Antilock brakes help
avoid only the braking skid.
Off-Road Driving Four-wheel-drive vehicles can be
used for off-road driving. Vehicles
without four-wheel drive and vehicles not equipped with All
Terrain (AT) or On-Off Road (OOR)
tires must not be driven off-road
except on a level, solid surface. For
contact information about the
original equipment tires, see the
warranty manual.
One of the best ways for successful
off-road driving is to control the
speed.
{ WarningWhen driving off-road, bouncing
and quick changes in direction
can easily throw you out of
position. This could cause you to
lose control and crash. You and
your passengers should always
wear seat belts.
Before Driving Off-Road
.
Have all necessary maintenance
and service work completed.
.
Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 195Warning (Continued)descending a hill and use a low
gear to keep vehicle speed under
control.
If the vehicle stalls on a hill:
1. Apply the brakes to stop the
vehicle, and then apply the
parking brake.
2. Shift into P (Park) and then
restart the engine.
.
If driving uphill when the
vehicle stalls, shift to
R (Reverse), release the
parking brake, and back
straight down.
.
Never try to turn the vehicle
around. If the hill is steep
enough to stall the vehicle,
it is steep enough to cause
it to roll over.
.
If you cannot make it up the
hill, back straight down
the hill. .
Never back down a hill in
N (Neutral) using only the
brake. The vehicle can roll
backward quickly and you
could lose control.
.
If driving downhill when the
vehicle stalls, shift to a
lower gear, release the
parking brake, and drive
straight down the hill.
3. If the vehicle cannot be
restarted after stalling, set the
parking brake, shift into
P (Park), and turn the
vehicle off.
3.1. Leave the vehicle and
seek help.
3.2. Stay clear of the path the
vehicle would take if it
rolled downhill.
.
Avoid turns that take the vehicle
across the incline of the hill.
A hill that can be driven straight
up or down might be too steep to
drive across. Driving across an
incline puts more weight on the downhill wheels, which could
cause a downhill slide or a
rollover.
.
Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the tires to slip sideways,
downhill. If the vehicle slips
sideways, it can hit something
that will trip it — a rock, a rut,
etc. — and roll over.
.
Hidden obstacles can make the
steepness of the incline more
severe. If a rock is driven across
with the uphill wheels, or if the
downhill wheels drop into a rut
or depression, the vehicle can tilt
even more.
.
If an incline must be driven
across, and the vehicle starts to
slide, turn downhill. This should
help straighten out the vehicle
and prevent the side slipping.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
196 Driving and Operating
{ WarningGetting out of the vehicle on the
downhill side when stopped
across an incline is dangerous.
If the vehicle rolls over, you could
be crushed or killed. Always get
out on the uphill side of the
vehicle and stay well clear of the
rollover path.
Driving in Mud, Sand, Snow,
or Ice Use a low gear when driving in
mud — the deeper the mud, the
lower the gear. Keep the vehicle
moving to avoid getting stuck.
Traction changes when driving on
sand. On loose sand, such as on
beaches or sand dunes, the tires
tend to sink into the sand. This
affects steering, accelerating, and
braking. Drive at a reduced speed
and avoid sharp turns or abrupt
maneuvers. Traction is reduced on hard packed
snow and ice and it is easy to lose
control. Reduce vehicle speed when
driving on hard packed snow
and ice.
{ WarningDriving on frozen lakes, ponds,
or rivers can be dangerous. Ice
conditions vary greatly and the
vehicle could fall through the ice;
you and your passengers could
drown. Drive your vehicle on safe
surfaces only.
Driving in Water
{ Warning
Driving through rushing water can
be dangerous. Deep water can
sweep your vehicle downstream
and you and your passengers
could drown. If it is only shallow
water, it can still wash away the
ground from under your tires.
(Continued) Warning (Continued) Traction could be lost, and the
vehicle could roll over. Do not
drive through rushing water.
CautionDo not drive through standing
water if it is deep enough to cover
the wheel hubs, axles, or exhaust
pipe. Deep water can damage the
axle and other vehicle parts.
If the standing water is not too deep,
drive through it slowly. At faster
speeds, water can get into the
engine and cause it to stall. Stalling
can occur if the exhaust pipe is
under water. Do not turn off the
ignition when driving through water.
If the exhaust pipe is under water,
the engine will not start. When going
through water, the brakes get wet
and it may take longer to stop. See
“ Driving on Wet Roads ” later in this
section.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 199.
Allow greater following distance
and watch for slippery spots. Icy
patches can occur on otherwise
clear roads in shaded areas.
The surface of a curve or an
overpass can remain icy when
the surrounding roads are clear.
Avoid sudden steering
maneuvers and braking while
on ice.
.
Turn off cruise control.
Blizzard Conditions Stop the vehicle in a safe place and
signal for help. Stay with the vehicle
unless there is help nearby.
If possible, use Roadside
Assistance. See Roadside
Assistance Program 0 390 . To get
help and keep everyone in the
vehicle safe:
.
Turn on the hazard warning
flashers.
.
Tie a red cloth to an outside
mirror. { WarningSnow 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.
If the vehicle is stuck in snow:
.
Clear snow from the base of
the vehicle, especially any
blocking the exhaust pipe.
.
Open a window about 5 cm
(2 in) on the vehicle side
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 circulate the air
inside the vehicle and set
(Continued) Warning (Continued) the fan speed to the highest
setting. See “ Climate
Control Systems. ”
For more information about CO,
see Engine Exhaust 0 215 .
To save fuel, run the engine for
short periods to warm the vehicle
and then shut the engine off and
partially close the window. Moving
about to keep warm also helps.
If it takes time for help to arrive,
when running 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 with the headlamps.
Do this as little as possible, to
save fuel.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
204 Driving and Operating Using heavier suspension
components to get added
durability might not change the
weight ratings. Ask your dealer
to help load the vehicle the
right way.
{ Warning
Things you put inside the
vehicle can strike and injure
people in a sudden stop or
turn, or in a crash. .
Put things in the cargo
area of the vehicle. Try to
spread the weight evenly..
Never stack heavier
things, like suitcases,
inside the vehicle so that
some of them are above
the tops of the seats.
.
Do not leave an
unsecured child restraint
in the vehicle.
(Continued) Warning (Continued) .
When you carry
something inside the
vehicle, secure it
whenever you can. .
Do not leave a seat
folded down unless you
need to.
There is also important loading
information for off-road driving in
this manual. See “ Loading Your
Vehicle for Off-Road Driving ”
under Off-Road Driving 0 192 .Starting and
Operating New Vehicle Break-In CautionThe vehicle does not need an
elaborate break-in. But it will
perform better in the long run if
you follow these guidelines:
.
Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 mi).
.
Do not drive at any one
constant speed, fast or slow,
for the first 805 km (500 mi).
Do not make full-throttle
starts. Avoid downshifting to
brake or slow the vehicle.
.
Avoid making hard stops for
the first 322 km (200 mi) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
206 Driving and Operating To shift out of P (Park), the ignition
must be on or in ACC/
ACCESSORY, and the brake pedal
must be applied.
Stopping the Engine/LOCK/
OFF (No Indicator Lights) : When
the vehicle is stopped, press
ENGINE START/STOP once to turn
the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0 212 .
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
turn off.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags. The vehicle may have an electric
steering column lock. The lock is
activated when the ignition is turned
off and either front door is opened.
A sound may be heard as the lock
actuates or releases. The steering
column lock may not release with
the wheels turned off center. If this
happens, the vehicle may not start.
Move the steering wheel from left to
right while attempting to start the
vehicle. If this does not work, the
vehicle needs service.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady
pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral).
This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to
a safe location.
3. Come to a complete stop, shift
to P (Park), and turn the
ignition off. On vehicles with an automatic transmission, the
shift lever must be in P (Park)
to turn the ignition off.
4. Set the parking brake. See
Parking Brake 0 228 .
{ WarningTurning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
press and hold ENGINE START/
STOP for longer than two seconds,
or press twice in five seconds.
ACC/ACCESSORY (Amber
Indicator Light) : This mode allows
some electrical accessories to be
used when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 207The ignition will switch from ACC/
ACCESSORY to off after
five minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator
Light) : This mode is for driving and
starting. With the ignition off, and
the brake pedal applied, pressing
the button once will turn the ignition
on. Once engine cranking begins,
release the button. Engine cranking
will continue until the engine starts.
See Starting the Engine 0 209 .
Service Mode
This power mode is available for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. With the vehicle off, and
the brake pedal not applied,
pressing and holding the button for
more than five seconds will place
the vehicle in Service Mode. The
instruments and audio systems will
operate as they do when the ignition
is on, but the vehicle will not be able to be driven. The engine will not
start in Service Mode. Press the
button again to turn the ignition off.
Ignition Positions (Key
Access)
Vehicles with Key Access have an
ignition switch with four different
positions.
To shift out of P (Park), the ignition
must be on or in ACC/ACCESSORY
and the regular brake pedal must be
applied.
0 (STOPPING THE ENGINE/LOCK/
OFF) : When the vehicle is stopped,
turn the ignition switch to LOCK/ OFF to turn the engine off. Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0 212 .
This position locks the ignition and
steering wheel. It also locks the
transmission on automatic
transmission vehicles. The key can
be removed in LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
does not work, then the vehicle
needs service.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady
pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.