2017 GMC SIERRA DENALI check engine

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Instruments and Controls 143
Passenger Airbag Status
Indicator If the vehicle has the passenger
sensing system, the overhead
console will have a passenger
airbag status indicator. See
Passenger Sensing System 0 81 for
important safety information.
United States
Canada and Mexico
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF, or the symbol
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 either 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 Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
144 Instruments and Controls 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.
See Battery Voltage and Charging
Messages 0 157 .
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
ON/RUN and the engine is not
running. See Ignition Positions
0 274 . 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
0 357 .
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 Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Instruments and Controls 145If 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:
.
A loose or missing fuel cap may
cause the light to come on. See
Filling the Tank 0 317 . A few
driving trips with the cap
properly installed may turn the
light off.
.
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
0 315 .
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 0 350 . 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 ON/RUN
while the engine is off.
.
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.
Brake System Warning
Light The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Instruments and Controls 149This 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 0 299 .
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. See Ride Control System
Messages 0 161 .
If the light is on and flashing, the
TCS and/or the StabiliTrak system
is actively working.
See Traction Control/Electronic
Stability Control 0 299 .
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.
CautionThe 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 0 376 .
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 0 376 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
150 Instruments and Controls
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 0 164 .
Stop as soon as possible, and
inflate the tires to the pressure value
shown on the Tire and Loading
Information label. See Tire Pressure
0 408 . 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 0 411 .
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Instruments and Controls 159obstructions, 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.
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.
See Engine Coolant Temperature
Gauge 0 138 . 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 OVERHEATING 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 0 138 .
When towing, use Tow/Haul mode
to prevent damage to the engine or
transmission. See Tow/Haul Mode
0 288 .
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 0 367 for
information on how to reset the
message.
See Engine Oil 0 364 and
Maintenance Schedule 0 455 .
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 0 364 .
ENGINE OIL HOT IDLE
ENGINE
This message displays when the
engine oil becomes hotter than the
normal operating temperature. Stop

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
160 Instruments and Controls and allow the vehicle to idle until it
cools down. See Engine Coolant
Temperature Gauge 0 138 .
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 0 364 .
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 0 376 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, or displays
repeatedly, 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 0 136 and Fuel
0 315 .
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 (Check Engine Light) 0 144 . Reinstall the fuel cap fully. See
Filling the Tank 0 317 . 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.
Key and Lock Messages REPLACE BATTERY IN
REMOTE KEY This message displays if a Remote
Keyless Entry (RKE) transmitter
battery is low. The battery needs to
be replaced in the transmitter. See
“ Battery Replacement ” under
Remote Keyless Entry (RKE)
System Operation 0 36 .
Lamp Messages TURN SIGNAL ON
This message displays and a chime
sounds if a turn signal is left on for
1.2 km (0.75 mi). Move the turn
signal lever to the off position.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
162 Instruments and Controls SERVICE TRACTION
CONTROL This message displays when there
is a problem with the Traction
Control System (TCS). When this
message displays, the system will
not limit wheel spin. Adjust your
driving accordingly. See your dealer
for service. See Traction Control/
Electronic Stability Control 0 299 .
STABILITRAK INITIALIZING This message may come on if the
StabiliTrak system has not fully
initialized because of road
conditions or the incorrect tire size.
When the StabiliTrak system is fully
initialized, the message will turn off.
See Traction Control/Electronic
Stability Control 0 299 . If this
message continues to be displayed
for multiple ignition cycles and on
different road surfaces, see your
dealer for service.
TRACTION CONTROL OFF
This message displays when the
traction control has been turned off.
See Traction Control/Electronic
Stability Control 0 299 . TRACTION CONTROL ON This message displays when the
traction control is active. See
Traction Control/Electronic Stability
Control 0 299 .
STABILITRAK OFF This message displays when the
StabiliTrak system has been turned
off. Adjust your driving accordingly.
To limit wheel spin and realize the
full benefits of the stability
enhancement system, you should
normally leave StabiliTrak on. See
Traction Control/Electronic Stability
Control 0 299 .
STABILITRAK OFF may also
display when the stability control
has been automatically disabled.
The following conditions can cause
this message to appear:
.
The system is overheating,
which could occur if StabiliTrak
activates continuously for an
extended period of time.
.
The brake system warning light
is on. See Brake System
Warning Light 0 145 . .
The stability system takes longer
than usual to complete its
diagnostic checks due to driving
conditions.
.
An engine or vehicle-related
problem has been detected and
the vehicle needs service. See
your dealer.
.
The transfer case is in
Four-Wheel Drive Low.
The message turns off as soon as
the conditions that caused the
message to be displayed are no
longer present.
Airbag System Messages SERVICE AIRBAG This message displays if there is a
problem with the airbag system.
Take the vehicle to your dealer for
service.