2020 GMC SIERRA DENALI check engine light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Introduction 7
16. Trailer Brake Control Panel (IfEquipped). See “Integrated
Trailer Brake Control System”
under Towing Equipment
0 296.
17. ENGINE START/STOP. See Ignition Positions (Keyless
Access) 0208 or
Ignition Positions (Key Access)
0 210.
18. Steering Wheel Controls (If Equipped). See the
infotainment manual.
Driver Information Center (DIC)
Controls. See Driver
Information Center (DIC) (Base
Level) 0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
19. Horn 0119.
20. Hood Release. See Hood
0 330.
21. Steering Wheel Adjustment
0118 (Out of View). 22.
Cruise Control 0243.
Adaptive Cruise Control (1500
Series) 0245 (If Equipped).
Forward Collision Alert (FCA)
System 0268 (If Equipped).
Heated Steering Wheel 0119
(If Equipped).
23. Data Link Connector (DLC) (Out of View). See Malfunction
Indicator Lamp (Check Engine
Light) 0137.
24. Electric Parking Brake 0233.
25. Fog Lamps 0170 (If
Equipped).
Instrument Panel Illumination
Control 0172.
Exterior Cargo Lamps 0171.
Exterior Lamp Controls 0165.
Task Lighting 0171 (If
Equipped).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
38 Keys, Doors, and Windows
The system does not have to be
manually armed or disarmed.
The vehicle is automatically
immobilized when the vehicle is
turned off.
The system is automatically
disarmed when the ignition is turned
from off to on.
The security light, in the instrument
cluster, comes on if there is a
problem with arming or disarming
the theft-deterrent system.
The system has one or more RKE
transmitters matched to an
immobilizer control unit in your
vehicle. Only a correctly matched
RKE transmitter will start the
vehicle. If the transmitter is ever
damaged, you may not be able to
start your vehicle.
When trying to start the vehicle, the
security light may come 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 vehicle will not change ignition
modes (ACC/ACCESSORY, on, off),
and the RKE transmitter appears to
be undamaged, try another
transmitter. Or, you may try placing
the transmitter in the transmitter
pocket located in the center
console. See
Remote Keyless Entry
(RKE) System Operation (Key
Access) 013 or
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 16.
If the ignition mode will not change
with the other transmitter or with the
transmitter in the transmitter pocket,
your vehicle needs service. If the
ignition does change modes, the
first transmitter may be faulty. See
your dealer who can service the
theft-deterrent system and have a
new RKE transmitter programmed to
the vehicle. It is possible for the immobilizer
system to learn new or replacement
RKE transmitters. Up to eight
transmitters can be programmed for
the vehicle. To program additional
transmitters, see "Programming
Transmitters to the Vehicle" under
Remote Keyless Entry (RKE)
System Operation (Key Access)
0
13 or
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 16
Do not leave the transmitter or
device that disarms or deactivates
the vehicle theft system in the
vehicle.
When equipped with a key, 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 0370.
If the engine still does not start with
the other key, the vehicle needs

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Instruments and Controls 117
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . 118
Steering Wheel Controls . . . . . . 119
Heated Steering Wheel . . . . . . . 119
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Windshield Wiper/Washer . . . . 119
Compass . . . . . . . . . . . . . . . . . . . . . 120
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 120
Power Outlets . . . . . . . . . . . . . . . . 121
Wireless Charging . . . . . . . . . . . . 122
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . 125
Instrument Cluster . . . . . . . . . . . . 126
Speedometer . . . . . . . . . . . . . . . . . 130
Odometer . . . . . . . . . . . . . . . . . . . . . 131
Trip Odometer . . . . . . . . . . . . . . . . 131
Tachometer . . . . . . . . . . . . . . . . . . . 131
Fuel Gauge . . . . . . . . . . . . . . . . . . . 131
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 132
Engine Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 133 Voltmeter Gauge . . . . . . . . . . . . . 134
Seat Belt Reminders . . . . . . . . . 135
Airbag Readiness Light . . . . . . . 135
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . 136
Charging System Light . . . . . . . 137
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . 137
Brake System Warning Light . . . . . . . . . . . . . . . . . . . . . . . . 139
Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . 140
Service Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . 140
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . 140
Four-Wheel-Drive Light . . . . . . . 141
Tow/Haul Mode Light . . . . . . . . . 141
Hill Descent Control Light . . . . 141
Lane Departure Warning (LDW) Light (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 141
Lane Keep Assist (LKA) Light (1500 Series) . . . . . . . . . . . . . . . 142
Vehicle Ahead Indicator . . . . . . 142
Pedestrian Ahead Indicator . . . 142
Traction Off Light . . . . . . . . . . . . . 142
Traction Control System (TCS)/ Electronic Stability Control
Light . . . . . . . . . . . . . . . . . . . . . . . . 143 Electronic Stability Control
(ESC) Off Light . . . . . . . . . . . . . . 143
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . 144
Driver Mode Control Light . . . . 144
Tire Pressure Light . . . . . . . . . . . 144
Engine Oil Pressure Light
(Uplevel Cluster) . . . . . . . . . . . . 145
Low Fuel Warning Light . . . . . . 145
Security Light . . . . . . . . . . . . . . . . . 146
High-Beam On Light . . . . . . . . . . 146
Front Fog Lamp Light . . . . . . . . . 146
Lamps On Reminder . . . . . . . . . 146
Cruise Control Light . . . . . . . . . . 146
Door Ajar Light . . . . . . . . . . . . . . . 147
Information Displays
Driver Information Center (DIC) (Base Level) . . . . . . . . . . . . . . . . 147
Driver Information Center (DIC) (Midlevel and Uplevel) . . . . . . 148
Head-Up Display (HUD) . . . . . . 152
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . 155
Engine Power Messages . . . . . 155
Vehicle Speed Messages . . . . . 156
Vehicle Personalization
Vehicle Personalization . . . . . . . 156

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Instruments and Controls 125
THIS SOFTWARE IS PROVIDED
BY THE COPYRIGHT HOLDERS
AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT
NOT LIMITED TO, THE IMPLIED
WARRANTIES OF
MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT
SHALL THE COPYRIGHT HOLDER
OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL,
EXEMPLARY, OR
CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF
SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA,OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY
OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF
THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.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 Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Instruments and Controls 133
Midlevel English Shown, BaseLevel and Uplevel Similar
The engine oil pressure gauge
shows the engine oil pressure
in kPa (kilopascals) or psi (pounds
per square inch) when the engine is
running.
Oil pressure can vary with engine
speed, outside temperature, coolant
temperature, and oil viscosity.
On some models, the oil pump will
vary engine oil pressure according
to engine needs. Oil pressure may
change quickly as the engine speed
or load varies. This is normal. If the
oil pressure warning light or Driver Information Center (DIC) message
indicates oil pressure outside the
normal operating range, check the
vehicle's oil as soon as possible.
See
Engine Oil 0339.
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.
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Engine Coolant
Temperature Gauge
Midlevel Metric Shown, Base Level and Uplevel Similar

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Instruments and Controls 137
Warning (Continued)
away. SeeAirbag Readiness
Light 0135 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
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.
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 on
and the engine is not running. See
Ignition Positions (Keyless Access)
0
208 or
Ignition Positions (Key Access)
0 210.
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.
Caution
If 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
138 Instruments and Controls
Caution
Modifications 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
0329.
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. 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 funnel
adapter, make sure that it has
been removed. See “Filling the
Tank with a Portable Gas Can”
under Filling the Tank (Pickup
Model) 0283 or
Filling the Tank (Chassis Cab
Model) 0285. 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
Recommended Fuel (Except
6.2L V8 Engine) 0280 or
Recommended Fuel (6.2L
V8 Engine) 0281.
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).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Instruments and Controls 145
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. SeeTire
Pressure 0387.
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 0390.Engine Oil Pressure Light
(Uplevel Cluster)
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
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.