2013 GMC YUKON light

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Instruments and Controls 5-17
The airbag readiness light comes on
for several seconds when the
vehicle is started. If the light does
not come on then, have it fixed
immediately.
{WARNING
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
See
Airbag System Messages on
page 5‑41.
Passenger Airbag Status
Indicator
If the vehicle has the airbag status
indicator pictured in the following
illustration, then the vehicle has a
passenger sensing system for the
right front passenger position. The
passenger airbag status indicator is
on the overhead console. See
Passenger Sensing System on
page 3‑36 for important safety
information.
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visors
refers to “ADVANCED AIRBAGS.”
United States
Canada
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF, or the
symbols for on and off, for several
seconds as a system check. If you
are using remote start, if equipped,
to start the vehicle from a distance,
you may not see the system check.
Then, after several more seconds,
the status indicator will light either
ON or OFF, or either the on or off

Black plate (18,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
5-18 Instruments and Controls
symbol to let you know the status of
the right front passenger frontal
airbag.
If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the right
front passenger frontal airbag is
enabled (may inflate).
If the word OFF or the off symbol is
lit on the airbag status indicator, it
means that the passenger sensing
system has turned off the right front
passenger frontal airbag.
If, after several seconds, both status
indicator lights remain on, or if there
are no lights at all, there may be a
problem with the lights or the
passenger sensing system. See
your dealer for service.{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. SeeAirbag Readiness
Light on page 5‑16 for more
information, including important
safety information.
Charging System Light
This light comes on briefly when the
ignition key is turned to START, 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.
The light should go out once the
engine starts. If it stays on,
or comes on while driving, there
could be a problem with the
charging system. A charging system
message in the Driver Information
Center (DIC) can also appear. See
Battery Voltage and Charging
Messages on page 5‑35 for more
information. This light could indicate
that there are problems with a
generator drive belt, or that there is
an electrical problem. Have it

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Instruments and Controls 5-19
checked right away. If the vehicle
must be driven a short distance with
the light on, turn off accessories,
such as the radio and air
conditioner.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors the operation
of the vehicle to ensure emissions
are at acceptable levels, helping to
maintain a clean environment. The
malfunction indicator lamp comes
on when the vehicle is placed in
ON/RUN, as a check to show it is
working. If it does not, have the
vehicle serviced by your dealer. See
Ignition Positions on page 9‑22.
If the malfunction indicator lamp
comes on while the engine is
running, this indicates that the OBD
II system has detected a problem
and diagnosis and service might be
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 also
assists the service technician in
correctly diagnosing any
malfunction.Notice:
If the vehicle is
continually driven with this light
on, 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.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
5-20 Instruments and Controls
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.
To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the
amount of cargo being hauled as
soon as it is possible.
If the light continues to flash, find a
safe place to stop and park the
vehicle. Turn the vehicle off, wait at
least 10 seconds, and restart the
engine. If the light is still flashing,
follow the previous steps and see
your dealer for service as soon as
possible. Light On Steady:
An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required.
The following may correct an
emission control system
malfunction:
.Check that the fuel cap is fully
installed. See Filling the Tank on
page 9‑60. The diagnostic
system can determine if the fuel
cap has been left off or
improperly installed. A loose or
missing fuel cap allows fuel to
evaporate into the atmosphere.
A few driving trips with the cap
properly installed should turn the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration, or stumbling on acceleration.
These conditions might go away
once the engine is warmed up.
If one or more of these conditions
occurs, change the fuel brand used.
It may require at least one full tank
of the proper fuel to turn the light off.
See Recommended Fuel on
page 9‑58.
If none of the above have made the
light turn off, your dealer can check
the vehicle. The dealer has the
proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.
Emissions Inspection and
Maintenance Programs
Depending on where you live, your
vehicle may be required to
participate in an emission control
system inspection and maintenance
program. For the inspection, the
emission system test equipment will
likely connect to the vehicle's Data
Link Connector (DLC).

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Instruments and Controls 5-21
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. 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 canhappen 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.
This light can also come on due to
low brake fluid. See
Brake Fluid on
page 10‑23 for more information.MetricEnglish
This light comes on briefly when the
ignition key is turned to ON/RUN.
If it does not come on then, have it
fixed so it is ready to warn if there is
a problem.

Black plate (22,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
5-22 Instruments and Controls
{WARNING
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push
or might go closer to the floor. It can
take longer to stop. If the light is still
on, have the vehicle towed for
service. See Towing the Vehicle on
page 10‑83.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the
ignition off. If the light comes on
while driving, stop as soon as it is
safely possible and turn the ignition
off. Then start the engine again to
reset the system. If the ABS light
stays on, or comes on again while
driving, the vehicle needs service.
If the regular brake system warning
light is not on, the vehicle still has
brakes, but not antilock brakes. If the regular brake system warning
light is also on, the vehicle does not
have antilock brakes and there is a
problem with the regular brakes.
See
Brake System Warning Light on
page 5‑21.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑35 for
all brake‐related DIC messages.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Instruments and Controls 5-23
For more information, seeTow/Haul
Mode on page 9‑33.
StabiliTrak®OFF Light
This light comes on briefly while
starting the engine.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light then goes off.
Press and release the Traction
Control System (TCS)/StabiliTrak
button to turn off TCS, and a
message displays in the DIC.
Press and briefly hold the TCS/
StabiliTrak button to turn off the
StabiliTrak system; the StabiliTrak
Off light comes on and a message
appears in the Driver Information
Center (DIC). If the StabiliTrak/TCS system is off,
the system does not assist in
controlling the vehicle. Turn on the
StabiliTrak/TCS system and the
indicator light turns off.
See
StabiliTrak
®System on
page 9‑43, and Ride Control System
Messages on page 5‑40 for more
information.
Traction Control System
(TCS)/StabiliTrak®Light
The TCS/StabiliTrak light comes on
briefly when the engine is started.
If the light does not come on or
stays on, have the vehicle serviced
by the dealer. If the system is
working normally, the indicator light
turns off. If the light comes on and stays on
while driving, and a message
displays in the Driver Information
Center (DIC), have the vehicle
serviced by the dealer. See
Ride
Control System Messages on
page 5‑40 for more information.
If the light flashes while driving, this
means that StabiliTrak or TCS is
assisting in controlling the vehicle.
See StabiliTrak
®System on
page 9‑43 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.

Black plate (24,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
5-24 Instruments and Controls
When the Light Is On Steady
This indicates that one or more of
the tires are significantly
underinflated.
A Driver Information Center (DIC)
tire pressure message may also
display. SeeTire Messages on
page 5‑42. 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 10‑50.
When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light
will come on at every ignition cycle.
See Tire Pressure Monitor
Operation on page 10‑52.Engine Oil Pressure Light
Notice: Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine
oil low can also damage the
engine. The repairs would not be
covered by the vehicle warranty.
Check the oil level as soon as
possible. Add oil if required, but
if the oil level is within the
operating range and the oil
pressure is still low, have the
vehicle serviced. Always follow
the maintenance schedule for
changing engine oil.
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer. If the system is working
normally the indicator light then
goes off. If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and it might
have some other system problem.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Low Fuel Warning Light
This light, under the fuel gauge,
comes on briefly while the engine is
being started.
This light and a chime come on
when the fuel tank is low on fuel.
The Driver Information Center also
displays a FUEL LEVEL LOW
message. See
Fuel System
Messages on page 5‑38 for more
information. When fuel is added this