2018 GMC YUKON XL warning light

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
146 Instruments and Controls 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
0 145 .
Four-Wheel-Drive Light
The four-wheel-drive light comes on
when the transfer case is shifted
into four-wheel drive and the front
axle engages. LO or HI will also be
next to this light when the vehicle is
in four-wheel low or four-wheel high.
Some delay between the shifting
and the light coming on is normal.
See Four-Wheel Drive 0 222 .Tow/Haul Mode Light For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
See Tow/Haul Mode 0 222 .
Lane Keep Assist (LKA)
Light
This light is green if LKA is available
to assist.
LKA may assist by gently turning
the steering wheel if the vehicle
approaches a detected lane marking without using the turn signal in that
direction. The LKA light will turn
amber.
This light is amber and flashes as a
Lane Departure Warning (LDW)
alert, to indicate that the lane
marking has been crossed.
See Lane Keep Assist (LKA) 0 252 .
Vehicle Ahead Indicator
If equipped, this indicator will
display green when a vehicle is
detected ahead and amber when
you are following a vehicle ahead
much too closely.
See Forward Collision Alert (FCA)
System 0 246 .

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
148 Instruments and Controls See Traction Control/Electronic
Stability Control 0 229 .
Engine Coolant
Temperature Warning
Light
This light comes on briefly while
starting the vehicle.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light goes off.
Caution
The engine coolant temperature
warning light indicates that the
vehicle has overheated. Driving
with this light on can damage the
(Continued) Caution (Continued) engine and it may not be covered
by the vehicle warranty. See
Engine Overheating 0 294 .
The engine coolant temperature
warning light comes on when the
engine has overheated.
If this happens, pull over and turn
off the engine as soon as possible.
See Engine Overheating 0 294 .
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. Stop as soon as possible,
and inflate the tires to the pressure
value shown on the Tire and
Loading Information label. See Tire
Pressure 0 327 .
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 0 330 .

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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
170 Lighting
Lighting Exterior Lighting Exterior Lamp Controls . . . . . . . 170
Exterior Lamps Off
Reminder . . . . . . . . . . . . . . . . . . . 172
Headlamp High/Low-Beam
Changer . . . . . . . . . . . . . . . . . . . . 172
Flash-to-Pass . . . . . . . . . . . . . . . . 172
Daytime Running
Lamps (DRL) . . . . . . . . . . . . . . . 173
Automatic Headlamp
System . . . . . . . . . . . . . . . . . . . . . . 173
Hazard Warning Flashers . . . . . 174
Turn and Lane-Change
Signals . . . . . . . . . . . . . . . . . . . . . . 174
Fog Lamps . . . . . . . . . . . . . . . . . . . 175 Interior Lighting Instrument Panel Illumination
Control . . . . . . . . . . . . . . . . . . . . . . 176
Dome Lamps . . . . . . . . . . . . . . . . . 176
Reading Lamps . . . . . . . . . . . . . . 176
Lighting Features Entry Lighting . . . . . . . . . . . . . . . . 177
Exit Lighting . . . . . . . . . . . . . . . . . . 177
Battery Load Management . . . 177
Battery Power Protection . . . . . 178
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . 178
Exterior Lighting Exterior Lamp Controls
The exterior lamp control is on the
instrument panel to the left of the
steering wheel.
There are four positions:
O : Turns off the automatic
headlamps and Daytime Running
Lamps (DRL). Turn the headlamp
control to
O again to turn the
automatic headlamps or DRL
back on.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
174 Lighting is in the full bright position. See
Instrument Panel Illumination
Control 0 176 .
When it is bright enough outside,
the headlamps will turn off or may
change to Daytime Running
Lamps (DRL).
The automatic headlamp system
turns off when the exterior lamp
control is turned to
O or the ignition
is off.
Lights On with Wipers If the windshield wipers are
activated in daylight with the engine
on, and the exterior lamp control is
in AUTO, the headlamps, parking
lamps, and other exterior lamps
come on. The transition time for the
lamps coming on varies based on
wiper speed. When the wipers are
not operating, these lamps turn off.
Move the exterior lamp control to
Oor
; to disable this feature. Hazard Warning Flashers
| : Press this button to make the
front and rear turn signal lamps
flash on and off. Press again to turn
the flashers off.
When the hazard warning flashers
are on, the vehicle's turn signals will
not work. Turn and Lane-Change
Signals
An arrow on the instrument cluster
flashes in the direction of the turn or
lane change.
Move the turn signal lever all the
way up or down to signal a turn.
Raise or lower the lever for less
than one second until the arrow
starts to flash to signal a lane
change. This causes the turn
signals to automatically flash three
times. It will flash six times if Tow/
Haul Mode is active. Holding the
turn signal lever for more than
one second will cause the turn
signals to flash until the lever is
released.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
194 Driving and Operating Warning (Continued)of control. Driving across hills can
cause a rollover. You could be
injured or killed. Do not drive on
steep hills.
Before driving on a hill, assess the
steepness, traction, and
obstructions. If the terrain ahead
cannot be seen, get out of the
vehicle and walk the hill before
driving further.
When driving on hills:
.
Use a low gear and keep a firm
grip on the steering wheel.
.
Maintain a slow speed.
.
When possible, drive straight up
or down the hill.
.
Slow down when approaching
the top of the hill.
.
Use headlamps even during the
day to make the vehicle more
visible. { WarningDriving to the top of a hill at high
speed can cause an accident.
There could be a drop-off,
embankment, cliff, or even
another vehicle. You could be
seriously injured or killed. As you
near the top of a hill, slow down
and stay alert.
.
Never go downhill forward or
backward with either the
transmission or transfer case in
N (Neutral). The brakes could
overheat and you could lose
control.
{ Warning
If the vehicle has the two-speed
automatic or electronic transfer
case, shifting the transfer case to
N (Neutral) can cause your
vehicle to roll even if the
transmission is in P (Park). This is
because the N (Neutral) position
(Continued) Warning (Continued) on the transfer case overrides the
transmission. You or someone
else could be injured. If leaving
the vehicle, set the parking brake
and shift the transmission to
P (Park). Shift the transfer case to
any position but N (Neutral).
.
When driving down a hill, keep
the vehicle headed straight
down. Use a low gear because
the engine will work with the
brakes to slow the vehicle and
help keep the vehicle under
control.
{ Warning
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and you or
others could be injured or killed.
Apply the brakes lightly when
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 197After Off-Road Driving Remove any brush or debris that
has collected on the underbody or
chassis, or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand,
have the brake linings cleaned and
checked. These substances can
cause glazing and uneven braking.
Check the body structure, driveline,
steering, suspension, wheels, tires,
and exhaust system for damage and
check the fuel lines and cooling
system for any leakage.
More frequent maintenance service
is required. See the Maintenance
Schedule 0 370 .
Driving on Wet Roads Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep-standing or flowing water. { WarningWet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road is wet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips Besides slowing down, other wet
weather driving tips include:
.
Allow extra following distance.
.
Pass with caution.
.
Keep windshield wiping
equipment in good shape.
.
Keep the windshield washer fluid
reservoir filled.
.
Have good tires with proper
tread depth. See Tires 0 320 .
.
Turn off cruise control.