
Black plate (20,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-20 Instruments and Controls
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 9-63.
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).
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 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.

Black plate (21,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-21
Brake System Warning
Light
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, there
is a brake problem. Have the brake
system inspected right away.
MetricEnglish
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 10-91.
{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
(Continued)
Warning (Continued)
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 the light does not come on, have it
fixed so it will be ready to warn if
there is a problem.
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

Black plate (23,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-23
This light changes to amber and
flashes to indicate that the lane
marking has been crossed without
using a turn signal in that direction.
SeeLane Departure Warning (LDW)
on page 9-61.
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 on page 9-59.
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 on page 9-49.
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 9-49.

Black plate (24,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-24 Instruments and Controls
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.If the indicator/warning light is on
and flashing, the TCS and/or the
StabiliTrak system is actively
working.
See
Traction Control/Electronic
Stability Control on page 9-49.
Engine Coolant
Temperature Warning
Light
This light comes on briefly while
starting the vehicle.
If it does not, have the vehicle
serviced by the 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
engine and it may not be covered
by the vehicle warranty. See
Engine Overheating on
page 10-21.
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 on
page 10-21.

Black plate (25,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-25
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. SeeTire Messages on
page 5-38. 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 10-59. 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 10-62.
Engine Oil Pressure Light
{Caution
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 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

Black plate (26,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-26 Instruments and Controls
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
on page 2-13.
High-Beam On Light
This light comes on when the
high-beam headlamps are in use.
See Headlamp High/Low-Beam
Changer on page 6-2.
Front Fog Lamp Light
For vehicles with fog lamps, this
light comes on when the fog lamps
are on.
The light goes out when the fog
lamps are turned off. See Fog
Lamps on page 6-5 for more
information.
Lamps On Reminder
This light comes on when the
exterior lamps are in use. See
Exterior Lamp Controls on page 6-1.

Black plate (29,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-29
Fuel Range and Instantaneous
Fuel Economy:Shows the
approximate distance the vehicle
can be driven without refueling.
LOW will be displayed when the
vehicle is low on fuel. The fuel
range estimate is based on an
average of the vehicle's fuel
economy over recent driving history
and the amount of fuel remaining in
the fuel tank. It also shows if the
Active Fuel Management is active
and in V4 mode, or inactive and in
V8 mode. See Active Fuel
Management
®on page 9-32.
The Instantaneous Fuel Economy
display shows the approximate
current fuel economy in either liters
per 100 kilometers (L/100 km) or
miles per gallon (mpg). This number
reflects only the approximate fuel
economy that the vehicle has right
now and changes frequently as
driving conditions change. Timer and Fuel Used:
This display
can be used as a timer. To start the
timer, press
Vwhile this display is
active. The display will show the
amount of time that has passed
since the timer was last reset. To
stop the timer, press
Vbriefly while
this display is active and the timer is
running.
This also shows the number of
liters (L) or gallons (gal) of fuel used
since the last reset of this
menu item.
Press and hold
Vwhile this display
is active to reset the timer and fuel
used. Each of these items can be
reset individually by pressing
p
while this display is active.
Oil Life: Shows an estimate of the
oil's remaining useful life.
If REMAINING OIL LIFE 99% is
displayed, that means 99% of the
current oil life remains. When the remaining oil life is low,
the CHANGE ENGINE OIL SOON
message will appear on the display.
See
Engine Oil Messages on
page 5-34. The oil should be
changed as soon as possible. See
Engine Oil on page 10-8. In addition
to the engine oil life system
monitoring the oil life, additional
maintenance is recommended in the
Maintenance Schedule. See
Maintenance Schedule on
page 11-3.
The Oil Life display must be reset
after each oil change. It will not
reset itself. Do not to reset the Oil
Life display at any time other than
when the oil has just been changed.
It cannot be reset accurately until
the next oil change. To reset the
engine oil life system, press and
hold
Vfor several seconds while
the Oil Life display is active. See
Engine Oil Life System on
page 10-11.

Black plate (30,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-30 Instruments and Controls
Tire Pressure:Shows the
approximate pressures of all four
tires. Tire pressure is displayed in
either kilopascal (kPa) or in pounds
per square inch (psi). If the pressure
is low, the value for that tire is
shown in amber. See Tire Pressure
Monitor System on page 10-61 and
Tire Pressure Monitor Operation on
page 10-62.
Best Fuel Economy: Displays
average fuel economy, the best fuel
economy over the selected
distance, and a bar graph showing
instantaneous fuel economy.
Press
pto change the selected
distance. Press and hold
Vwhile
this display is active to reset the
best fuel economy and average fuel
economy. This display can also be
reset by selecting reset in the menu.
Top Consumers: Shows a list of
the features that are currently
impacting the fuel economy, in order
from highest to lowest. If a feature is
turned off, it will be removed from
the list. Economy Trend:
Shows history of
the Average Fuel Economy from the
last 50 km (30 mi). Each bar
represents about 5 km (3 mi) of
driving. During driving the bars will
shift to always reflect the most
recent distance on the right side.
Press and hold
Vto clear the graph
or press
pto reset through
the menu.
ECO Index: The bar graph
provides feedback on the efficiency
of current driving behavior. The
graph shows a value that is based
on current fuel consumption
compared to what is expected from
the vehicle with good and bad
driving habits. It also shows if the
Active Fuel Management is active
and in V4 mode, or inactive and in
V8 mode. See Active Fuel
Management
®on page 9-32.
Engine Hours: Shows the total
number of hours the engine has run.
This display also shows the engine
idle hours. Trailer Brake:
On vehicles with the
Integrated Trailer Brake Control
(ITBC) system, the trailer brake
display appears in the DIC.
TRAILER GAIN shows the trailer
gain setting. This setting can be
adjusted from 0.0 to 10.0 with either
a trailer connected or disconnected.
OUTPUT shows the power output to
the trailer any time a trailer with
electric brakes is connected. Output
is displayed as a bar graph. Dashes
may appear in the OUTPUT display.
Speed Signs: Shows sign
information, which comes from a
roadway database in the onboard
navigation.
Following Distance: Used to
select the alert timing for the
Forward Collision Alert (FCA). See
Forward Collision Alert (FCA)
System on page 9-59.
Blank Page: Shows no
information.