
Black plate (50,1)GMC Yukon/Yukon XL Owner Manual - 2011
3-50 Seats and Restraints
6. Restart the vehicle.The passenger sensing system
may or may not turn off the
airbag for a child in a child
restraint depending upon the
child’s seating posture and body
build. It is better to secure the
child restraint in a rear seat.
If the Off Indicator is Lit for an
Adult-Size Occupant
If a person of adult size is sitting in
the right front passenger seat, but
the off indicator is lit, it could be because that person is not sitting
properly in the seat. If this happens,
use the following steps to allow the
system to detect that person and
enable the right front passenger
frontal airbag:
1. Turn the vehicle off.
2. Remove any additional material
from the seat, such as blankets,
cushions, seat covers, seat
heaters, or seat massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on the seat
cushion, with legs comfortably
extended.
5. Restart the vehicle and have the person remain in this position for
two to three minutes after the on
indicator is lit.
Additional Factors Affecting
System Operation
Safety belts help keep the
passenger in position on the
seat during vehicle maneuvers
and braking, which helps the
passenger sensing system
maintain the passenger airbag
status. See “Safety Belts” and
“Child Restraints” in the Index for
additional information about the
importance of proper restraint use.
If the shoulder portion of the belt
is pulled out all the way, the child
restraint locking feature will be
engaged. This may unintentionally
cause the passenger sensing
system to turn the airbag off for
some adult‐size occupants. If this
happens, let the belt go back all the
way and start again.

Black plate (53,1)GMC Yukon/Yukon XL Owner Manual - 2011
Seats and Restraints 3-53
Q: Because I have a disability,I have to get my vehicle
modified. How can I find out
whether this will affect my
airbag system?
A: If you have questions, call
Customer Assistance. The
phone numbers and addresses
for Customer Assistance are
in Step Two of the Customer
Satisfaction Procedure in
this manual. See Customer
Satisfaction Procedure on
page 13‑1.
In addition, your dealer and the
service manual have information
about the location of the airbag
sensors, sensing and diagnostic
module and airbag wiring.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance
or replacement. Make sure the
airbag readiness light is working. See
Airbag Readiness Light on
page 5‑18 for more information.
Notice: If an airbag covering is
damaged, opened, or broken, the
airbag may not work properly.
Do not open or break the airbag
coverings. If there are any
opened or broken airbag covers,
have the airbag covering and/or
airbag module replaced. For the
location of the airbag modules,
see What Makes an Airbag
Inflate? on page 3‑44. See your
dealer for service.
Replacing Airbag System
Parts After a Crash
{WARNING
A crash can damage the
airbag systems in the vehicle.
A damaged airbag system
may not work properly and
may not protect you and your
passenger(s) in a crash, resulting
(Continued)
WARNING (Continued)
in serious injury or even death.
To help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.
If an airbag inflates, you will need to
replace airbag system parts. See
your dealer for service.
If the airbag readiness light stays
on after the vehicle is started or
comes on when you are driving,
the airbag system may not work
properly. Have the vehicle serviced
right away. See Airbag Readiness
Light on page 5‑18 for more
information.

Black plate (54,1)GMC Yukon/Yukon XL Owner Manual - 2011
3-54 Seats and Restraints
Child Restraints
Older Children
Older children who have outgrown
booster seats should wear the
vehicle safety belts.The manufacturer's instructions that
come with the booster seat state the
weight and height limitations for that
booster. Use a booster seat with
a lap-shoulder belt until the child
passes the fit test below:
.Sit all the way back on the seat.
Do the knees bend at the seat
edge? If yes, continue. If no,
return to the booster seat.
.Buckle the lap-shoulder belt.
Does the shoulder belt rest on
the shoulder? If yes, continue.
If no, try using the rear safety
belt comfort guide. See
“Rear
Safety Belt Comfort Guides”
under Lap-Shoulder Belt on
page 3‑30 for more information.
If the shoulder belt still does not
rest on the shoulder, then return
to the booster seat.
.Does the lap belt fit low and
snug on the hips, touching the
thighs? If yes, continue. If no,
return to the booster seat.
.Can proper safety belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.
Q: What is the proper way to wear safety belts?
A: An older child should wear a
lap-shoulder belt and get the
additional restraint a shoulder
belt can provide. The shoulder
belt should not cross the face
or neck. The lap belt should fit
snugly below the hips, just
touching the top of the thighs.
This applies belt force to the
child's pelvic bones in a crash.
It should never be worn over the
abdomen, which could cause
severe or even fatal internal
injuries in a crash.
Also see “Rear Safety Belt Comfort
Guides” underLap-Shoulder Belt on
page 3‑30.

Black plate (16,1)GMC Yukon/Yukon XL Owner Manual - 2011
5-16 Instruments and Controls
A reading in the low pressure zone
may be caused by a dangerously
low oil level or some other problem
causing low oil pressure. Check the
oil as soon as possible.
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Engine Coolant
Temperature Gauge
Metric
English
This gauge shows the engine
coolant temperature.
It also provides an indicator of how
hard the vehicle is working. During a
majority of the operation, the gauge
reads 100°C (210°F) or less. If you
are pulling a load or going up hills,
it is normal for the temperature to
fluctuate and approach the 122°C
(250°F) mark. If the gauge reaches
the 125°C (260°F) mark, it indicates
that the cooling system is working
beyond its capacity.

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2011
Instruments and Controls 5-21
Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors operation of
the fuel, ignition, and emission
control systems. It ensures that
emissions are at acceptable levels
for the life of the vehicle, helping to
produce a cleaner environment.
This light should come on when the
ignition is on, but the engine is not
running, as a check to show it is
working. If it does not, have the
vehicle serviced by your dealer.If the malfunction indicator lamp
comes on and stays on while the
engine is running, this indicates that
there is an OBD II problem and
service is required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the service technician in correctly
diagnosing any malfunction.
Notice:
If the vehicle is
continually driven with this
light on, after a while, the
emission controls might not
work as well, the vehicle fuel
economy might not be as good,
and the engine might not run
as smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. Notice:
Modifications made
to the engine, transmission,
exhaust, intake, or fuel system
of the vehicle or the replacement
of the original tires with other
than those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered
by the vehicle warranty. This
could also result in a failure
to pass a required Emission
Inspection/Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire
condition has been detected.
A misfire increases vehicle
emissions and could damage the
emission control system on the
vehicle. Diagnosis and service
might be required.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2011
Instruments and Controls 5-23
Emissions Inspection and
Maintenance Programs
Some state/provincial and local
governments may have programs
to inspect the on-vehicle emission
control equipment. For the
inspection, the emission system
test equipment is connected
to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUN
while the engine is off.
.The critical emission control
systems have not been
completely diagnosed by the
system. This can happen if
the battery has recently been
replaced or if the battery has
run down. The diagnostic
system evaluates critical
emission control systems during
normal driving. This can take
several days of routine driving.
If this has been done and the
vehicle still does not pass the
inspection, your dealer can
prepare the vehicle for
inspection.
Brake System Warning
Light
With the ignition on, the brake
system warning light comes on
when the parking brake is set. If the
vehicle is driven with the parking
brake engaged, a chime sounds
when the vehicle speed is greater
than 8 km/h (5 mph).
The vehicle brake system
consists of two hydraulic circuits.
If one circuit is not working, the
remaining circuit can still work to
stop the vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on and
a chime sounds there could be a
brake problem. Have the brake
system inspected right away.

Black plate (26,1)GMC Yukon/Yukon XL Owner Manual - 2011
5-26 Instruments and Controls
The light flashes if the system is
active and is working to assist the
driver with directional control of the
vehicle in difficult driving conditions.
SeeStabiliTrak
®System on
page 9‑52 for more information.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine
is started. It provides information
about tire pressures and the TPMS. When the Light is On Steady
This indicates that one or more
of the tires are significantly
underinflated.
A tire pressure message can
accompany the light. See
Tire
Messages on page 5‑45 for more
information. Stop as soon as
possible, and inflate the tires to the
pressure value shown on the Tire
and Loading Information label. See
Tire Pressure on page 10‑56 for
more information.
When the Light Flashes First and
Then is On Steady
This indicates that there may be a
problem with the TPMS. The light
flashes for about a minute and
stays on steady for the remainder
of the ignition cycle. This sequence
repeats with every ignition cycle.
See Tire Pressure Monitor
Operation on page 10‑59 for more
information.
Engine Oil Pressure Light
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine
oil maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.

Black plate (32,1)GMC Yukon/Yukon XL Owner Manual - 2011
5-32 Instruments and Controls
This display shows the
instantaneous fuel economy in
liters per 100 kilometers (L/100 km)
or miles per gallon (mpg). Unlike
average economy, this screen
cannot be reset.
An Active Fuel Management
indicator will display on the right
side of the DIC, while INST ECON
displays on the left side. Active
Fuel Management allows the
engine to operate on either four or
eight cylinders, depending on your
driving demands. When Active
Fuel Management is active, V4 will
display on the DIC. When Active
Fuel Management is inactive,
V8 will display. SeeActive Fuel
Management
®on page 9‑35 for
more information.
Blank Display
This display shows no information.
Vehicle Information Menu
Items (With DIC Buttons)
T(Vehicle Information): Press
to scroll through the following menu
items:
Oil Life
Press the vehicle information
button until OIL LIFE REMAINING
displays. This display shows an
estimate of the oil's remaining
useful life. If you see 99% OIL LIFE
REMAINING on the display, that
means 99% of the current oil life
remains. The engine oil life system
will alert you to change the oil on
a schedule consistent with your
driving conditions. When the remaining oil life is low,
the CHANGE ENGINE OIL SOON
message will appear on the display.
See
“CHANGE ENGINE OIL SOON”
under Engine Oil Messages on
page 5‑41. You should change the
oil as soon as you can. See Engine
Oil on page 10‑7. In addition to the
engine oil life system monitoring the
oil life, additional maintenance is
recommended in the Maintenance
Schedule in this manual. See
Scheduled Maintenance on
page 11‑2 for more information.
Remember, you must reset the OIL
LIFE display yourself after each oil
change. It will not reset itself. Also,
be careful not to reset the OIL LIFE
display accidentally at any time
other than when the oil has just
been changed. It cannot be reset
accurately until the next oil change.
To reset the engine oil life system,
see Engine Oil Life System on
page 10‑10.