2012 GMC YUKON open hood

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2012
Keys, Doors, and Windows 2-7
The vehicle cannot be remote
started if the key is in the ignition,
the hood is not closed, or if there is
an emission control system
malfunction and the check engine
light is on.
Also, the engine will turn off during a
remote vehicle start if the coolant
temperature gets too high or if the
oil pressure gets low.
Remote Start Ready
If the vehicle does not have the
remote vehicle start feature, it may
have the remote start ready feature.
This feature allows your dealer to
add the manufacturer's remote
vehicle start feature.
See your dealer to add the
manufacturer's remote vehicle start
feature to the vehicle.
Door Locks
{WARNING
Unlocked doors can be
dangerous.
.Passengers, especially
children, can easily open the
doors and fall out of a moving
vehicle. When a door is
locked, the handle will not
open it. The chance of being
thrown out of the vehicle in a
crash is increased if the
doors are not locked. So, all
passengers should wear
safety belts properly and the
doors should be locked
whenever the vehicle is
driven.(Continued)
WARNING (Continued)
.Young children who get into
unlocked vehicles may be
unable to get out. A child can
be overcome by extreme heat
and can suffer permanent
injuries or even death from
heat stroke. Always lock the
vehicle whenever leaving it.
.Outsiders can easily enter
through an unlocked door
when you slow down or stop
the vehicle. Locking the doors
can help prevent this from
happening.
There are several ways to lock and
unlock the vehicle.
From outside, use the Remote
Keyless Entry (RKE) transmitter or
the key in the driver door.

Black plate (39,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-39
See“Integrated Trailer Brake
Control System” underTowing
Equipment on page 9‑76 for more
information.
Door Ajar Messages
DRIVER DOOR OPEN
This message displays and a chime
sounds if the driver door is not fully
closed and the vehicle is shifted out
of P (Park). Stop and turn off the
vehicle, check the door for
obstructions, and close the door
again. Check to see if the message
still appears on the DIC.
HOOD OPEN
This message displays and a chime
sounds if the hood is not fully
closed. Stop and turn off the
vehicle, check the hood for
obstructions, and close the hood
again. Check to see if the message
still appears on the DIC.
LEFT REAR DOOR OPEN
This message displays and a chime
sounds if the driver side rear door is
not fully closed and the vehicle is
shifted out of P (Park). Stop and turn
off the vehicle, check the door for
obstructions, and close the door
again. Check to see if the message
still appears on the DIC.
PASSENGER DOOR OPEN
This message displays and a chime
sounds if the front passenger door
is not fully closed and the vehicle is
shifted out of P (Park). Stop and turn
off the vehicle, check the door for
obstructions, and close the door
again. Check to see if the message
still appears on the DIC.
REAR ACCESS OPEN
This message displays and a chime
sounds if the liftgate or liftglass is
open while the ignition is in ON/
RUN. Turn off the vehicle and check
the liftgate and liftglass. Restart the
vehicle and check for the message
on the DIC display.
RIGHT REAR DOOR OPEN
This message displays and a chime
sounds if the passenger side rear
door is not fully closed and the
vehicle is shifted out of P (Park).
Stop and turn off the vehicle, check
the door for obstructions, and close
the door again. Check to see if the
message still appears on the DIC.
Engine Cooling System
Messages
ENGINE HOT A/C (Air
Conditioning) TURNED OFF
This message displays when the
engine coolant becomes hotter than
the normal operating temperature.
See Engine Coolant Temperature
Gauge on page 5‑16. To avoid
added strain on a hot engine, the air
conditioning compressor
automatically turns off. When the
coolant temperature returns to
normal, the air conditioning
compressor turns back on. You can
continue to drive your vehicle.

Black plate (26,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-26 Driving and Operating
Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below−18°C (0°F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. An internal thermostat in
the plug-end of the cord may exist
which will prevent engine coolant
heater operation at temperatures
above −18°C (0°F).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap
the electrical cord. The cord
is secured to the Engine
Compartment Fuse Block with a
clip. Carefully remove the wire
tie which secures the electrical
cord. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
(Continued)
WARNING (Continued)
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.

Black plate (62,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-62 Driving and Operating
Vehicles that have a FlexFuel badge
and a yellow fuel cap can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
SeeFuel E85 (85% Ethanol) on
page 9‑64. For all other vehicles,
use only the unleaded gasoline
described under Recommended
Fuel on page 9‑62.
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise,
commonly referred to as spark
knock, might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.
Gasoline Specifications
(U.S. and Canada Only)
At a minimum, gasoline should
meet ASTM specification
D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See Fuel Additives
on page 9‑63 for additional
information.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle might fail a smog‐check test.
See
Malfunction Indicator Lamp on
page 5‑21. If this occurs, return to
your authorized dealer for diagnosis.
If it is determined that the condition
is caused by the type of fuel used,
repairs might not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
Never use leaded gasoline or any
other fuel not recommended in the
previous text on fuel. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty.
To check the fuel availability, ask an
auto club, or contact a major oil
company that does business in the
country where you will be driving.

Black plate (5,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-5
Hood
To open the hood:
1. Pull the handle with this symbolon it. It is located inside the
vehicle to the lower left of the
steering wheel.
2. Then go to the front of thevehicle and locate the secondary
hood release, near the center of
the grille. 3. Push the secondary hood
release to the right.
4. Lift the hood. Before closing the hood, be sure
all the filler caps are on properly.
Then bring the hood from full
open to within 152 mm (6 in)
from the closed position, pause,
then push the front center of the
hood with a swift, firm motion to
fully close the hood.

Black plate (22,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-22 Vehicle Care
Then check to see if the engine
cooling fans are running. If the
engine is overheating, both fans
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
Notice:Engine damage from
running the engine without
coolant is not covered by the
vehicle warranty. See Overheated
Engine Protection Operating
Mode on page 10‑23 for
information on driving to a safe
place in an emergency.
Notice: If the engine catches fire
while driving with no coolant, the
vehicle can be badly damaged.
The costly repairs would not be
covered by the vehicle warranty.
See Overheated Engine
Protection Operating Mode on
page 10‑23 for information on
driving to a safe place in an
emergency.If Steam Is Coming from the
Engine Compartment
{WARNING
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Turn it off
and get everyone away from the
vehicle until it cools down. Wait
until there is no sign of steam or
coolant before you open
the hood.
If you keep driving when the
vehicles engine is overheated,
the liquids in it can catch fire. You
or others could be badly burned.
Stop the engine if it overheats,
and get out of the vehicle until the
engine is cool.
(Continued)
WARNING (Continued)
SeeOverheated Engine
Protection Operating Mode on
page 10‑23 for information on
driving to a safe place in an
emergency.
If No Steam Is Coming from
the Engine Compartment
The ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem.
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.

Black plate (35,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-35
Headlamp Aiming
The vehicle has a visual optical
headlamp aiming system. The aim
of the headlamps has been preset
at the factory and should need no
further adjustment.
However, if the vehicle is damaged
in a crash, the aim of the headlamps
may be affected and adjustment
may be necessary.
If oncoming vehicles flash their high
beams at you, this may mean the
vertical aim of the headlamps needs
to be adjusted.
It is recommended that the vehicle
be taken to the dealer for service if
the headlamps need to be adjusted.
It is possible, however, to re-aim the
headlamps as described.The vehicle should:.Be placed so the headlamps
are 7.6 m (25 ft) from a
light‐colored wall.
.Have all four tires on a level
surface which is level all the way
to the wall.
.Be placed so it is perpendicular
to the wall.
.Not have any snow, ice, or mud
on it.
.Be fully assembled and all other
work stopped while headlamp
aiming is being performed.
.Be loaded with a full tank of fuel
and one person or 75 kg
(160 lbs) sitting on the
driver seat.
.Have the tires properly inflated.
.Have the spare tire in its proper
location in the vehicle.Headlamp aiming is done with the
vehicle's low-beam headlamps. The
high-beam headlamps will be
correctly aimed if the low-beam
headlamps are aimed properly.
To adjust the vertical aim:
1. Open the hood. See
Hood on
page 10‑52. Locate the aim dot on the lens of the low‐beam headlamp.
3. Record the distance from the ground to the aim dot on the
low‐beam headlamp.

Black plate (89,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-89
2. Get the vehicles close enoughso the jumper cables can reach,
but be sure the vehicles are not
touching each other. If they
are, it could cause a ground
connection you do not want. You
would not be able to start your
vehicle, and the bad grounding
could damage the electrical
systems.
To avoid the possibility of the
vehicles rolling, set the parking
brake firmly on both vehicles
involved in the jump start
procedure. Put the automatic
transmission in P (Park) or a
manual transmission in
N (Neutral) before setting the
parking brake. If the vehicle has
a four-wheel-drive transfer case
with a N (Neutral) position, be
sure the transfer case is in a
drive gear, not in N (Neutral). Notice:
If any accessories are left
on or plugged in during the jump
starting procedure, they could be
damaged. The repairs would
not be covered by the vehicle
warranty. Whenever possible,
turn off or unplug all accessories
on either vehicle when jump
starting the vehicle.
3. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
cigarette lighter or the accessory
power outlets. Turn off the radio
and all the lamps that are not
needed. This avoids sparks and
helps save both batteries. And it
could save the radio! 4. Open the hood on the other
vehicle and locate the
positive (+) and negative (−)
terminal locations on that
vehicle.
Your vehicle has a remote
positive (+) jump starting
terminal and a remote
negative (−) jump starting
terminal. You should always use
these remote terminals instead
of the terminals on the battery.
If the vehicle has a remote
positive (+) terminal, it is located
under a red plastic cover at the
positive battery post. To uncover
the remote positive (+) terminal,
open the red plastic cover.