service GMC YUKON 2015 Owner's Guide

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
Instruments and Controls 5-19
a check to show the light is working.
It should go out when the engine is
started.
If the light stays on, or comes on
while driving, there may be a
problem with the electrical charging
system. Have it checked by your
dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is
flashing, the Driver Information
Center (DIC) also displays a
message.
SeeBattery Voltage and Charging
Messages on page 5-30.
If a short distance must be driven
with the light on, be sure to turn off
all accessories, such as the radio
and air conditioner.
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 (Key Access) on
page 9-20
orIgnition Positions
(Keyless Access) 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.
{Caution
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.
{Caution
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
(Continued)

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
5-20 Instruments and Controls
Caution (Continued)
(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.
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 9-72. 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 Fuel on page 9-70.
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

Black plate (22,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
5-22 Instruments and Controls
This light should come on briefly
when the engine is started. If it does
not come on then, have it fixed so it
will be ready to warn if there is a
problem.
When the ignition is on, the brake
system warning light also comes on
when the parking brake is set. The
light stays on if the parking brake
does not fully release. If it stays on
after the parking brake is fully
released, it means the vehicle has a
brake problem.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push,
or the pedal can go closer to the
floor. It may take longer to stop.
If the light is still on, have the
vehicle towed for service. See
Towing the Vehicle on page 10-80.{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.
Antilock Brake System
(ABS) Warning Light
This light comes on briefly when the
engine is started.
If it does not, have the vehicle
serviced by your dealer.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 off the vehicle. 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. A chime may
also sound when the light comes on
steady.
If the ABS light is the only light on,
the vehicle has regular brakes, but
the antilock brakes are not
functioning.
If both the ABS and the brake
system warning light are on, the
vehicle's antilock brakes are not
functioning and there is a problem
with the regular brakes. See your
dealer for service.
See
Brake System Warning Light on
page 5-21 andBrake System
Messages on page 5-31.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
Instruments and Controls 5-23
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
SeeTow/Haul Mode on page 9-35.
Hill Descent Control Light
If equipped, the Hill Descent Control
light comes on steady when the
system is ready for use. When the
light flashes, the system is active. See
Hill Descent Control (HDC) on
page 9-46.
Lane Departure Warning
(LDW) Light
If equipped, this light briefly comes
on while starting the vehicle.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light then turns off.
This light comes on green when the
system is on and ready to operate.
When the system determines that
the vehicle is leaving its lane
without using the turn signal, this
light will change to amber and flash.
See Lane Departure Warning (LDW)
on page 9-68.
Vehicle Ahead Indicator
If equipped, this light displays green
when a vehicle is detected ahead.
This light will display amber when
you are following a vehicle ahead
much too closely.
See Forward Collision Alert (FCA)
System on page 9-62.

Black plate (24,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
5-24 Instruments and Controls
Traction 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
turns off.
The traction off light comes on when
the Traction Control System (TCS)
has been turned off by pressing and
releasing the TCS/StabiliTrak
button.
This light and the StabiliTrak OFF
light come on when StabiliTrak is
turned off.
If the TCS is off, wheel spin is not
limited. Adjust driving accordingly.
SeeTraction Control/Electronic
Stability Control on page 9-44.
StabiliTrak®OFF Light
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer.
This light comes on when the
StabiliTrak system is turned off.
If StabiliTrak is off, the Traction
Control System (TCS) is also off.
If the StabiliTrak and TCS are off,
the system does not assist in
controlling the vehicle. Turn on the
TCS and the StabiliTrak systems
and the warning light turns off.
See Traction Control/Electronic
Stability Control on page 9-44.
Traction Control System
(TCS)/StabiliTrak®Light
This light comes on briefly when the
engine is started.
If the light does not come on, have
the vehicle serviced by your dealer.
If the system is working normally,
the indicator light turns off.
If the light is on and not flashing, the
TCS, and potentially the StabiliTrak
system have been disabled. A DIC
message may display. Check the
DIC messages to determine which
feature(s) is no longer functioning
and whether the vehicle requires
service.

Black plate (25,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
Instruments and Controls 5-25
If the indicator/warning light is on
and flashing, the TCS and/or the
StabiliTrak system is actively
working.
SeeTraction Control/Electronic
Stability Control on page 9-44.
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 Driver Information Center (DIC)
tire pressure message may also
display. See
Tire Messages on
page 5-39. 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 10-51.
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 10-54.
Low Fuel Warning Light
This light is near the fuel gauge and
comes on briefly when the ignition is
turned on as a check to show it is
working.
It also comes on when the fuel tank
is low on fuel. The light turns off
when fuel is added. If it does not,
have the vehicle serviced.
Security Light
The security light should come on
briefly as the engine is started. If it
does not come on, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light turns off.

Black plate (31,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
Instruments and Controls 5-31
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 cluster. SeeCharging
System Light on page 5-18. 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.
TRANSPORT MODE ON
This message is displayed when the
vehicle is in transport mode. Some
features can be disabled while in
this mode, including Remote
Keyless Entry (RKE), remote start,
and the vehicle alarm system. Take
the vehicle to your dealer for service
to turn transport mode off.
Brake System Messages
BRAKE FLUID LOW
This message is displayed when the
brake fluid level is low. See Brake
Fluid on page 10-21.
SERVICE BRAKE ASSIST
This message may be displayed
when there is a problem with the
brake boost assist system. When
this message is displayed, the brake
boost assist motor might be heard
operating and you might notice
pulsation in the brake pedal. This is
normal under these conditions. Take
the vehicle to your dealer for
service.
SERVICE TRAILER BRAKE
SYSTEM
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays and a chime
may sound 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.
See
“Integrated Trailer Brake
Control System” underTowing
Equipment on page 9-81 for more
information.
Compass Messages
Dashes may be displayed if the
vehicle temporarily loses
communication with the Global
Positioning System (GPS).

Black plate (32,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
5-32 Instruments and Controls
Cruise Control Messages
ADAPTIVE CRUISE SET
TO XXX
This message displays when the
Adaptive Cruise Control (ACC)
speed is set. SeeAdaptive Cruise
Control on page 9-51.
ADAPTIVE CRUISE
TEMPORARILY UNAVAILABLE
This message displays when
attempting to activate Adaptive
Cruise Control (ACC) when it is
temporarily unavailable. The ACC
system does not need service.
This can occur under the following
conditions:
.The radar is not clean. Keep the
radar sensors free of mud, dirt,
snow, ice, and slush. Clean the
entire front and/or rear of the
vehicle. For cleaning
instructions, see Exterior Care
on page 10-86.
.Heavy rain or snow is interfering
with the radar object detection or
camera performance.
CRUISE SET TO XXX
This message displays when the
cruise control speed is set. See
Cruise Control on page 9-48.
NO CRUISE BRAKING GAS
PEDAL APPLIED
This message displays when
Adaptive Cruise Control (ACC) is
active and the driver is pressing the
gas pedal. When this occurs, ACC
will not brake. See Adaptive Cruise
Control on page 9-51.
SERVICE ADAPTIVE CRUISE
CONTROL
If this message displays, take the
vehicle to your dealer to repair the
system. Adaptive Cruise Control
(ACC), Forward Collision Alert
(FCA), and/or the Active Emergency
Braking System may not work. Do
not use these systems until the
vehicle has been repaired.
SHIFT TO PARK BEFORE
EXITING
This message may display if
Adaptive Cruise Control (ACC) is
engaged holding the vehicle at a
stop, and the driver attempts to exit
the vehicle. Put the vehicle in
P (Park) before exiting.
Door Ajar Messages
DOOR OPEN
This message displays and a chime
may sound if a door is not fully
closed. 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
may sound 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.

Black plate (33,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
Instruments and Controls 5-33
REAR ACCESS OPEN
This message will display when the
liftgate is open. Close the liftgate
completely.
Engine Cooling System
Messages
A/C OFF DUE TO HIGH
ENGINE TEMP
This message displays when the
engine coolant becomes hotter than
the normal operating temperature.
SeeEngine Coolant Temperature
Gauge on page 5-15. 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.
If this message continues to appear,
have the system repaired by your
dealer as soon as possible to avoid
damage to the engine.
ENGINE OVERHEATED IDLE
ENGINE
This message displays when the
engine coolant temperature is too
hot. Stop and allow the vehicle to
idle until it cools down. See Engine
Coolant Temperature Gauge on
page 5-15.
When towing, use tow/haul mode to
prevent damage to the engine or
transmission. See Tow/Haul Mode
on page 9-35.
ENGINE OVERHEATED STOP
ENGINE
This message displays and a chime
may sound if the engine cooling
system reaches unsafe
temperatures for operation. Stop
and turn off the vehicle as soon as it
is safe to do so to avoid severe
damage. This message clears when
the engine has cooled to a safe
operating temperature.
Engine Oil Messages
CHANGE ENGINE OIL SOON
This message displays when the
engine oil needs to be changed.
When you change the engine oil, be
sure to reset the CHANGE ENGINE
OIL SOON message. See Engine
Oil Life System on page 10-9 for
information on how to reset the
message. See Engine Oil on
page 10-6 andMaintenance
Schedule on page 11-2.
ENGINE OIL LOW ADD OIL
On some vehicles, this message
displays when the engine oil level
may be too low. Check the oil level
before filling to the recommended
level. If the oil is not low and this
message remains on, take the
vehicle to your dealer for service.
See Engine Oil on page 10-6.

Black plate (34,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - crc - 6/5/14
5-34 Instruments and Controls
ENGINE OIL HOT IDLE
ENGINE
This message displays when the
engine oil becomes hotter than the
normal operating temperature. Stop
and allow the vehicle to idle until it
cools down. SeeEngine Coolant
Temperature Gauge on page 5-15.
OIL PRESSURE LOW STOP
ENGINE
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have the vehicle
serviced by your dealer. See Engine
Oil on page 10-6.
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays and a chime
may sound when the cooling system
temperature gets too hot and the
engine further enters the engine
coolant protection mode. See
Engine Overheating on page 10-18
for more information.
This message also displays when
the vehicle's engine power is
reduced. Reduced engine power
can affect the vehicle's ability to
accelerate. If this message is on,
but there is no reduction in
performance, proceed to your
destination. The performance may
be reduced the next time the vehicle
is driven. The vehicle may be driven
at a reduced speed while this
message is on, but acceleration and
speed may be reduced. Anytime
this message stays on, the vehicle
should be taken to your dealer for
service as soon as possible.
Fuel System Messages
FUEL LEVEL LOW
This message displays and a chime
may sound if the fuel level is low.
Refuel as soon as possible. See
Fuel Gauge on page 5-13 andFuel
on page 9-70.
TIGHTEN GAS CAP
This message may display along
with the malfunction indicator lamp
on the instrument cluster if the
vehicle's fuel cap is not tightened
properly. See Malfunction Indicator
Lamp on page 5-19. Reinstall the
fuel cap fully. See Filling the Tank
on page 9-72. 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 this light and message off.