check engine light GMC YUKON XL 2018 Owners Manual

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
In Brief 71. Air Vents 0 185 .
2. Head-Up Display (HUD) 0 154
(If Equipped).
3.
g Traction Control/Electronic
Stability Control 0 229 .
j Power Assist Steps 0 48 (If
Equipped).
X Parking Assist Button (If
Equipped). See Assistance
Systems for Parking or Backing
0 243 .
A Lane Departure Warning
(LDW) 0 252 (If Equipped).
0 Pedal Adjust Switch (If
Equipped). See Adjustable
Throttle and Brake Pedal
0 205 .
4. Turn Signal Lever. See Turn
and Lane-Change Signals
0 174 .
Windshield Wiper/Washer
0 123 . 5. Favorite Switches (Out of
View). See “ Steering Wheel
Controls ” in the infotainment
manual.
Volume Switches (Out of View).
See “ Steering Wheel Controls ”
in the infotainment manual.
6. Hazard Warning Flashers
0 174 .
7. Instrument Cluster 0 133 .
8. Shift Lever. See Automatic
Transmission 0 216 .
Tow/Haul Selector Button. See
Tow/Haul Mode 0 222 .
Range Selection Mode (If
Equipped). See Manual Mode
0 218 .
9. Light Sensor. See Automatic
Headlamp System 0 173 .
10. Infotainment 0 179 .
11. Dual Automatic Climate Control
System 0 180 .
12. Heated and Ventilated Front
Seats 0 67 . 13. Rear Climate Control Buttons.
See Rear Climate Control
System 0 184 .
14. Ignition Positions (Key Access)
0 207 or Ignition Positions
(Keyless Access) 0 205 .
15. Steering Wheel Controls. See
the infotainment manual.
16. Horn 0 123 .
17. Steering Wheel Adjustment
0 123 .
18. Hood Release. See Hood
0 279 .
19. Cruise Control 0 233 .
Adaptive Cruise Control 0 235
(If Equipped).
Forward Collision Alert (FCA)
System 0 246 (If Equipped).
Heated Steering Wheel 0 123 .
20. Trailer Brake Control Panel (If
Equipped). See Towing
Equipment 0 267 .
21. Data Link Connector (DLC)
(Out of View). See Malfunction
Indicator Lamp (Check Engine
Light) 0 143 .

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Keys, Doors, and Windows 43This can be manually overridden by
pressing and holding
Q on the
power door lock switch.
Keyless Access : When locking is
requested with the driver door open
and the vehicle is on or in ACC/
ACCESSORY, all the doors will lock
and then the driver door will unlock.
If the vehicle is off and locking is
requested while a door is open,
when all doors are closed the
vehicle will check for RKE
transmitters inside. If an RKE
transmitter is detected and the
number of RKE transmitters inside
has not reduced, the driver door will
unlock and the horn will sound three
times.
This can be manually overridden by
pressing and holding
Q on the
power door lock switch.
Unlocked Door Anti-Lockout
If Unlocked Door Anti-Lockout is
turned on and the vehicle is off, the
driver door is open, and locking is
requested, all the doors will lock and
the driver door will remain open.
Press the button again to lock the driver door. The Unlocked Door
Anti-Lockout feature can be turned
on or off. See Vehicle
Personalization 0 158 .
Safety Locks The rear door safety locks prevent
passengers from opening the rear
doors from inside the vehicle.
Press
{ to activate the safety locks
on the rear doors. The indicator light
comes on when activated.
Press
{ again to deactivate the
safety locks. Doors Liftgate
{ WarningExhaust gases can enter the
vehicle if it is driven with the
liftgate or trunk/hatch open,
or with any objects that pass
through the seal between the
body and the trunk/hatch or
liftgate. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
If the vehicle must be driven with
the liftgate or trunk/hatch open:
.
Close all of the windows.
.
Fully open the air outlets on
or under the instrument
panel.
.
Adjust the climate control
system to a setting that
brings in only outside air
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
52 Keys, Doors, and Windows When trying to start the vehicle, the
security light comes on briefly when
the ignition is turned on.
If the engine does not start and the
security light stays on, there is a
problem with the system. Turn the
ignition off and try again.
If the engine still does not start, and
the key appears to be undamaged,
try another ignition key. It may be
necessary to check the fuse. See
Fuses and Circuit Breakers 0 309 .
If the engine still does not start with
the other key, the vehicle needs
service. If the vehicle does start, the
first key may be faulty. See your
dealer. It is possible for the immobilizer
system to learn new or replacement
keys. Up to eight keys can be
programmed for the vehicle. To
program additional keys, see Keys
(Keyless Access) 0 27 or Keys (Key
Access) 0 28 . To program additional
transmitters, see your dealer.
Do not leave the key or device that
disarms or deactivates the vehicle
theft system in the vehicle.
See your dealer to get a new key
blank cut exactly as the ignition key
that operates the system. Exterior Mirrors Convex Mirrors
{ WarningA convex mirror can make things,
like other vehicles, look farther
away than they really are. If you
cut too sharply into the right lane,
you could hit a vehicle on the
right. Check the inside mirror or
glance over your shoulder before
changing lanes.
The passenger side mirror is convex
shaped. A convex mirror's surface is
curved so more can be seen from
the driver seat.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
122 Instruments and Controls
Instruments and
Controls Controls Steering Wheel Adjustment . . . 123
Steering Wheel Controls . . . . . . 123
Heated Steering Wheel . . . . . . . 123
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Windshield Wiper/Washer . . . . 123
Rear Window Wiper/
Washer . . . . . . . . . . . . . . . . . . . . . 125
Compass . . . . . . . . . . . . . . . . . . . . . 126
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 126
Power Outlets . . . . . . . . . . . . . . . . 127
Wireless Charging . . . . . . . . . . . . 129
Warning Lights, Gauges, and
Indicators Warning Lights, Gauges, and
Indicators . . . . . . . . . . . . . . . . . . . 132
Instrument Cluster . . . . . . . . . . . . 133
Speedometer . . . . . . . . . . . . . . . . . 136
Odometer . . . . . . . . . . . . . . . . . . . . . 136
Trip Odometer . . . . . . . . . . . . . . . . 136
Tachometer . . . . . . . . . . . . . . . . . . . 136
Fuel Gauge . . . . . . . . . . . . . . . . . . . 137
Engine Oil Pressure
Gauge . . . . . . . . . . . . . . . . . . . . . . 137 Engine Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 138
Transmission Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 139
Voltmeter Gauge . . . . . . . . . . . . . 140
Seat Belt Reminders . . . . . . . . . 140
Airbag Readiness Light . . . . . . . 141
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . 142
Charging System Light . . . . . . . 142
Malfunction Indicator Lamp
(Check Engine Light) . . . . . . . . 143
Brake System Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . 145
Antilock Brake System (ABS)
Warning Light . . . . . . . . . . . . . . . 145
Four-Wheel-Drive Light . . . . . . . 146
Tow/Haul Mode Light . . . . . . . . . 146
Lane Keep Assist (LKA)
Light . . . . . . . . . . . . . . . . . . . . . . . . 146
Vehicle Ahead Indicator . . . . . . 146
Traction Off Light . . . . . . . . . . . . . 147
StabiliTrak OFF Light . . . . . . . . . 147
Traction Control System (TCS)/
StabiliTrak Light . . . . . . . . . . . . . 147
Engine Coolant Temperature
Warning Light . . . . . . . . . . . . . . . 148
Tire Pressure Light . . . . . . . . . . . 148
Engine Oil Pressure Light . . . . 149
Low Fuel Warning Light . . . . . . 149
Security Light . . . . . . . . . . . . . . . . . 149 High-Beam On Light . . . . . . . . . . 149
Front Fog Lamp Light . . . . . . . . . 150
Lamps On Reminder . . . . . . . . . 150
Cruise Control Light . . . . . . . . . . 150
Door Ajar Light . . . . . . . . . . . . . . . 150
Information Displays Driver Information
Center (DIC) . . . . . . . . . . . . . . . . 151
Head-Up Display (HUD) . . . . . . 154
Vehicle Messages Vehicle Messages . . . . . . . . . . . . 157
Engine Power Messages . . . . . 158
Vehicle Speed Messages . . . . . 158
Vehicle Personalization Vehicle Personalization . . . . . . . 158
Universal Remote System Universal Remote System . . . . 166
Universal Remote System
Programming . . . . . . . . . . . . . . . 166
Universal Remote System
Operation . . . . . . . . . . . . . . . . . . . 168

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
132 Instruments and Controls
Warning Lights,
Gauges, and
Indicators Warning lights and gauges can
signal that something is wrong
before it becomes serious enough
to cause an expensive repair or
replacement. Paying attention to the
warning lights and gauges could
prevent injury.
Some warning lights come on briefly
when the engine is started to
indicate they are working. When
one of the warning lights comes on
and stays on while driving, or when
one of the gauges shows there may
be a problem, check the section that
explains what to do. Waiting to do
repairs can be costly and even
dangerous.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
142 Instruments and Controls
Passenger Airbag Status
Indicator The vehicle has a passenger
sensing system. See Passenger
Sensing System 0 91 for important
safety information. The passenger
airbag status indicator is in the
overhead console.
United States
Canada and Mexico
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. Then, after several more seconds, the
status indicator will light either ON
or OFF, or the on or off symbol, to
let you know the status of the front
outboard passenger frontal airbag.
If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the front
outboard passenger frontal airbag is
allowed to 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 front
outboard 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
(Continued) Warning (Continued) with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. See Airbag Readiness
Light 0 141 for more information,
including important safety
information.
Charging System Light
The charging system light comes on
briefly when the ignition is turned
on, but the engine is not running, as
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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Instruments and Controls 143system. 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.
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 (Check Engine
Light) This light is part of the vehicle ’ s
emission control on-board
diagnostic system. If this light is on
while the engine is running, a
malfunction has been detected and
the vehicle may require service. The
light should come on to show that it
is working when the ignition is in
Service Mode.
See Ignition Positions (Key Access)
0 207 or Ignition Positions (Keyless
Access) 0 205 . Malfunctions are often indicated by
the system before any problem is
noticeable. Being aware of the light
and seeking service promptly when
it comes on may prevent damage.
CautionIf the vehicle is driven continually
with this light on, the emission
control system may not work as
well, the fuel economy may be
lower, and the vehicle may not
run smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. CautionModifications to the engine,
transmission, exhaust, intake,
or fuel system, or the use of
replacement tires that do not
meet the original tire
specifications, can cause this light
to come on. This could lead to
costly repairs not covered by the
vehicle warranty. This could also
affect the vehicle ’ s ability to pass
an Emissions Inspection/
Maintenance test. See
Accessories and Modifications
0 278 .
If the light is flashing : A
malfunction has been detected that
could damage the emission control
system and increase vehicle
emissions. Diagnosis and service
may be required.
To help prevent damage, reduce
vehicle speed and avoid hard
accelerations and uphill grades.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
144 Instruments and Controls If towing a trailer, reduce the
amount of cargo being hauled as
soon as possible.
If the light continues to flash, find a
safe place to park. Turn the vehicle
off and wait at least 10 seconds
before restarting the engine. If the
light is still flashing, follow the
previous guidelines and see your
dealer for service as soon as
possible.
If the light is on steady : A
malfunction has been detected.
Diagnosis and service may be
required.
Check the following:
.
If fuel has been added to the
vehicle using the capless fuel
funnel adapter, make sure that it
has been removed. See “ Filling
the Tank with a Portable Gas
Can ” under Filling the Tank
0 256 . The diagnostic system
can detect if the adapter has
been left installed in the vehicle,
allowing fuel to evaporate into
the atmosphere. A few driving
trips with the adapter removed
may turn off the light. .
Poor fuel quality can cause
inefficient engine operation and
poor driveability, which may go
away once the engine is warmed
up. If this occurs, change the
fuel brand. It may require at
least one full tank of the proper
fuel to turn the light off. See Fuel
0 254 .
If the light remains on, see your
dealer.
Emissions Inspection and
Maintenance Programs If the vehicle requires an Emissions
Inspection/Maintenance test, the
test equipment will likely connect to
the vehicle's Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. Connecting devices that are not used to perform an Emissions
Inspection/Maintenance test or to
service the vehicle may affect
vehicle operation. See Add-On
Electrical Equipment 0 274 . See
your dealer if assistance is needed.
The vehicle may not pass
inspection if:
.
The light is on when the engine
is running.
.
The light does not come on
when the ignition is in
Service Mode.
.
Critical emission control systems
have not been completely
diagnosed. If this happens, the
vehicle would not be ready for
inspection and might require
several days of routine driving
before the system is ready for
inspection. This can happen if
the 12-volt battery has recently
been replaced or run down, or if
the vehicle has been recently
serviced.
See your dealer if the vehicle will
not pass or cannot be made ready
for the test.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Instruments and Controls 147
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.
See Traction Control/Electronic
Stability Control 0 229 . 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 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 0 229 .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 Driver Information Center (DIC)
message may display. Check the
DIC messages to determine which
feature(s) is no longer functioning
and whether the vehicle requires
service.
If the light is on and flashing, the
TCS and/or the StabiliTrak system
is actively working.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Instruments and Controls 149
Engine Oil Pressure Light CautionLack 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 should come on briefly as
the engine is started. If it does not
come on, have the vehicle serviced
by your dealer. 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 might have
some other system problem. See
your dealer.
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.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system. See Immobilizer Operation
0 51 .
High-Beam On Light