Black plate (35,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-35
The seat position sensor provides
information that is used to determine
if the airbags should deploy at a
reduced level or at full deployment.
The vehicle may or may not have
seat‐mounted side impact airbags.
The vehicle has roof-rail airbags.
SeeAirbag System on page 3‑30.
Seat‐mounted side impact airbags
and roof-rail airbags are intended to
inflate in moderate to severe side
crashes. In addition, these roof-rail
airbags are intended to inflate
during a rollover or in a severe
frontal impact. Seat‐mounted side
impact airbags and roof-rail airbags
will inflate if the crash severity is
above the system's designed
threshold level. The threshold level
can vary with specific vehicle
design.
Roof-rail airbags are not intended
to inflate in rear impacts. A
seat‐mounted side impact airbag is
intended to deploy on the side of the vehicle that is struck. Both roof-rail
airbags will deploy when either side
of the vehicle is struck or if the
sensing system predicts that the
vehicle is about to roll over, or in a
severe frontal impact.
In any particular crash, no one can
say whether an airbag should have
inflated simply because of the
damage to a vehicle or because of
what the repair costs were. For
frontal airbags, inflation is
determined by what the vehicle hits,
the angle of the impact, and how
quickly the vehicle slows down. For
seat‐mounted side impact and
roof-rail airbags, deployment is
determined by the location and
severity of the side impact. In a
rollover event, roof-rail airbag
deployment is determined by the
direction of the roll.What Makes an Airbag
Inflate?
In a deployment event, the sensing
system sends an electrical signal
triggering a release of gas from the
inflator. Gas from the inflator fills the
airbag causing the bag to break out
of the cover and deploy. The inflator,
the airbag, and related hardware are
all part of the airbag module.
Frontal airbag modules are located
inside the steering wheel and
instrument panel. For vehicles with
seat‐mounted side impact airbags,
there are airbags modules in the
side of the front seatbacks closest
to the door. For vehicles with
roof-rail airbags, there are airbag
modules in the ceiling of the vehicle,
near the side windows that have
occupant seating positions.
Black plate (36,1)GMC Yukon/Yukon XL Owner Manual - 2012
3-36 Seats and Restraints
How Does an Airbag
Restrain?
In moderate to severe frontal or
near frontal collisions, even belted
occupants can contact the steering
wheel or the instrument panel. In
moderate to severe side collisions,
even belted occupants can contact
the inside of the vehicle.
Airbags supplement the protection
provided by safety belts. Frontal
airbags distribute the force of the
impact more evenly over the
occupant's upper body, stopping
the occupant more gradually.
Seat‐mounted side impact and
roof-rail airbags distribute the force
of the impact more evenly over the
occupant's upper body.
Rollover capable roof-rail airbags
are designed to help contain the
head and chest of occupants in the
outboard seating positions in the
first, second, and third rows,if equipped with a third row seat.
The rollover capable roof-rail
airbags are designed to help reduce
the risk of full or partial ejection in
rollover events, although no system
can prevent all such ejections.
But airbags would not help in
many types of collisions, primarily
because the occupant's motion is
not toward those airbags. See
When
Should an Airbag Inflate? on
page 3‑34 for more information.
Airbags should never be regarded
as anything more than a supplement
to safety belts.
What Will You See after
an Airbag Inflates?
After the frontal airbags and
seat-mounted side impact airbags
inflate, they quickly deflate, so
quickly that some people may not
even realize an airbag inflated. Roof-rail airbags may still be at least
partially inflated for some time after
they deploy. Some components of
the airbag module may be hot for
several minutes. For location of the
airbag modules, see
What Makes
an Airbag Inflate? on page 3‑35.
The parts of the airbag that come
into contact with you may be warm,
but not too hot to touch. There may
be some smoke and dust coming
from the vents in the deflated
airbags. Airbag inflation does not
prevent the driver from seeing out of
the windshield or being able to steer
the vehicle, nor does it prevent
people from leaving the vehicle.
{WARNING
When an airbag inflates, there
may be dust in the air. This dust
could cause breathing problems
for people with a history of
asthma or other breathing trouble.
(Continued)
Black plate (43,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-43
keep the airbag system from
working properly. Changing or
moving any parts of the front
seats, safety belts, the airbag
sensing and diagnostic module,
steering wheel, instrument
panel, roof-rail airbag modules,
ceiling headliner or pillar garnish
trim, overhead console, front
sensors, side impact sensors,
or airbag wiring can affect the
operation of the airbag system.
In addition, the vehicle may have
a passenger sensing system for
the right front passenger's
position, which includes sensors
that are part of the passenger's
seat. The passenger sensing
system may not operate properly
if the original seat trim is
replaced with non-GM covers,
upholstery or trim, or with GM
covers, upholstery or trim
designed for a different vehicle.Any object, such as an
aftermarket seat heater or a
comfort enhancing pad or
device, installed under or on top
of the seat fabric, could also
interfere with the operation of
the passenger sensing system.
This could either prevent proper
deployment of the passenger
airbag(s) or prevent the
passenger sensing system from
properly turning off the
passenger airbag(s). See
Passenger Sensing System on
page 3‑38.
If you have any questions about
this, you should contact
Customer Assistance before you
modify your vehicle. 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. If the vehicle has rollover
roof-rail airbags, see
Different
Size Tires and Wheels on
page 10‑66 for additional
important information.
Q: What if I added a snow plow? Will it keep the airbags from
working properly?
A: We have designed our airbag
systems to work properly under
a wide range of conditions,
including snow plowing with
vehicles that have the optional
Snow Plow Prep Package
(RPO VYU). But do not change
or defeat the snow plow's
“tripping mechanism.” If you do,
it can damage your snow plow
and your vehicle, and it may
cause an airbag inflation.
Black plate (13,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-13
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Speedometer
The speedometer shows the
vehicle's speed in either kilometers
per hour (km/h) or miles per
hour (mph).
Odometer
The odometer shows how far the
vehicle has been driven, in either
kilometers or miles.
Trip Odometer
The trip odometer can show how far
the vehicle has been driven since
the trip odometer was last set
to zero.
Press the reset button, located on
the instrument panel cluster next to
the trip odometer display, to toggle
between the trip odometer and the
regular odometer. Holding the reset
button for approximately one second
while the trip odometer is displayed
resets it.
To display the odometer reading
with the ignition off, press the reset
button.
Tachometer
The tachometer displays the
engine speed in revolutions per
minute (rpm).
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-17
SeeEngine Overheating on
page 10‑21.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Voltmeter Gauge
When the engine is not running, but
the ignition is on, this gauge shows
the battery's state of charge in
DC volts. When the engine is running, the
gauge shows the condition of the
charging system. The charging
system regulates voltage based on
the state of the battery for improved
fuel economy and battery life. The
gauge may transition from a higher
to lower or a lower to higher
reading, this is normal. Readings
between the low and high warning
zones indicate the normal operating
range. The gauge may also read
low during the fuel economy mode,
this is normal.
Readings in the low warning zone
may occur when a large number of
electrical accessories are operating
in the vehicle and the engine is left
at an idle for an extended period.
This condition is normal since the
charging system is not able to
provide full power at engine idle. As
engine speeds are increased, this
condition should correct itself as
higher engine speeds allow the
charging system to create full
power. If there is a problem with the
battery charging system, this lightwill come on or the SERVICE
BATTERY CHARGING SYSTEM
DIC message will display. See
Battery Voltage and Charging
Messages on page 5‑38
and
Charging System Light on
page 5‑20 for more information.
Safety Belt Reminders
Driver Safety Belt Reminder
Light
There is a driver safety belt
reminder light on the instrument
panel cluster.
When the vehicle is started, this
light flashes and a chime may come
on to remind the driver to fasten
their safety belt. Then the light stays
on solid until the belt is buckled.
Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-23
Emissions Inspection and
Maintenance Programs
Some 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/RUNwhile the engine is off. See your
dealer for assistance in verifying
proper operation of the
malfunction indicator lamp.
.The OBD II (On-Board
Diagnostics) system determines
that critical emission control
systems have not been
completely diagnosed. The
vehicle would be considered not
ready for inspection. This can
happen if the 12-volt battery has
recently been replaced or run
down. The diagnostic system is
designed to evaluate 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 for lack of OBD II
system readiness, 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 (29,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-29
Information Displays
Driver Information
Center (DIC)
Your vehicle has a Driver
Information Center (DIC).
The DIC displays information about
your vehicle. It also displays
warning messages if a system
problem is detected.
All messages will appear in the
DIC display located below the
tachometer in the instrument panel
cluster.
The DIC comes on when the ignition
is on. After a short delay, the DIC
will display the information that was
last displayed before the engine
was turned off.The DIC has different displays
which can be accessed by pressing
the DIC buttons located on the
instrument panel, next to the
steering wheel. If the vehicle does
not have DIC buttons, the trip
odometer reset stem can be used to
access some of the menu items.
The DIC displays trip, fuel, and
vehicle system information, and
warning messages if a system
problem is detected.
The DIC also allows some features
to be customized. See
Vehicle
Personalization (With DIC Buttons)
on page 5‑47 for more information. DIC Buttons
The buttons are the trip/fuel, vehicle
information, customization, and set/
reset buttons. The button functions
are detailed in the following pages.
3(Trip/Fuel):
Press to display
the odometer, trip odometer, fuel
range, average economy, fuel
used, timer, instantaneous
economy and Active Fuel
Management™ indicator, and
transmission temperature.
Black plate (38,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-38 Instruments and Controls
Battery Voltage and
Charging Messages
BATTERY LOW START
VEHICLE
When the vehicle’s battery is
severely discharged, this message
will display and four chimes will
sound. Start the vehicle
immediately. If the vehicle is not
started and the battery continues to
discharge, the climate controls,
heated seats, and audio systems
will shut off and the vehicle may
require a jump start. These systems
will function again after the vehicle
is started.
SERVICE BATTERY
CHARGING SYSTEM
On some vehicles, this message
displays if there is a problem with
the battery charging system. Under
certain conditions, the charging
system light may also turn on in the
instrument panel cluster. See
Charging System Light on
page 5‑20. Driving with this problem could drain the battery. Turn off all
unnecessary accessories. Have the
electrical system checked as soon
as possible. See your dealer.
Brake System Messages
SERVICE BRAKE SYSTEM
This message displays along with
the brake system warning light if
there is a problem with the brake
system. See
Brake System Warning
Light on page 5‑23. If this message
appears, stop as soon as possible
and turn off the vehicle. Restart the
vehicle and check for the message
on the DIC display. If the message
is still displayed or appears again
when you begin driving, the brake
system needs service as soon as
possible. See your dealer.
SERVICE BRAKES SOON
This message displays if there is a
problem with the brake system.
If this message appears, stop as
soon as possible and turn off the
vehicle. Restart the vehicle and check for the message on the DIC
display. If the message is still
displayed or appears again when
you begin driving, the brake system
needs service. See your dealer.
SERVICE TRAILER BRAKE
SYSTEM
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays and a chime
sounds when there is a problem
with the ITBC system.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull your vehicle over to
the side of the road and turn the
ignition off. Check the wiring
connection to the trailer and turn the
ignition back on. If this message still
displays, either your vehicle or the
trailer needs service. See your
dealer.