Page 44 of 439

Black plate (13,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Keys, Doors, and Windows 2-13
manually overridden by pressing
and holding
Qon the power door
lock switch.
Pushbutton Start: When locking
is requested with the driver door
open and the vehicle is in ACC/
ACCESSORY or ON/RUN/START,
all the doors will lock and then the
driver door will unlock. This can be
manually overridden by pressing
and holding
Qon the power door
lock switch.
If Unlocked Door Anti-Lockout is
turned on, the vehicle is off with the
driver door open, and door locking
is requested, all the doors will lock
and only the driver door will unlock.
The Unlocked Door Anti-Lockout
feature can be turned on or off using
the vehicle personalization menus.
See Vehicle Personalization on
page 5-50.
Safety Locks
The rear door safety locks prevent
passengers from opening the rear
doors from inside the vehicle.
Press{to activate the safety locks
on the rear doors. The indicator light
comes on when activated.
Press
{again to deactivate the
safety locks.
Doors
Liftgate
{Warning
Exhaust gases can enter the
vehicle if it is driven with the
liftgate or trunk/hatch open,
or with any objects that pass
through the seal between the
body and the trunk/hatch or
liftgate. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
If the vehicle must be driven with
the liftgate or trunk/hatch open:
.Close all of the windows.
.Fully open the air outlets on
or under the instrument
panel.
(Continued)
Page 276 of 439

Black plate (69,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Driving and Operating 9-69
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10-81.
When replacing the fuel cap, insert
the tether in its hole before
tightening the cap. Turn the fuel cap
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. SeeMalfunction
Indicator Lamp on page 5-20.
The TIGHTEN GAS CAP message
displays if the fuel cap is not
properly installed.
{Warning
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
(Continued)
Warning (Continued)
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
{Caution
If a new fuel cap is needed, be
sure to get the right type of cap
from your dealer. The wrong type
of fuel cap may not fit properly,
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp on
page 5-20.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
.Use approved fuel
containers.
.Remove the container from
the vehicle, trunk, or pickup
bed before filling.
.Place the container on the
ground.
.Place the nozzle inside the fill
opening of the container
before dispensing fuel, and(Continued)
Page 278 of 439

Black plate (71,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Driving and Operating 9-71
{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
When towing a trailer:
.Do not drive with the liftgate,
trunk/hatch, or rear-most
window open.
.Fully open the air outlets on
or under the instrument
panel.
.Also adjust the climate
control system to a setting
that brings in only outside air.
See“Climate Control
Systems” in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9-28. Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. If the trailer has
electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination will not accelerate as
quickly and is longer so it is
necessary to go much farther
beyond the passed vehicle before
returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
{Caution
Making very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
(Continued)