ECO mode GMC SIERRA 2021 Owner's Manual

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Keys, Doors, and Windows 17
4. Place the new transmitter in thetransmitter pocket/insert.
5. Press ENGINE START/STOP. When the transmitter is learned, the DIC display
will show that it is ready to program the
next transmitter.
6. Remove the transmitter from the transmitter pocket and press
KorQon
the transmitter.
To program additional transmitters,
repeat Steps 4–6.
When all additional transmitters are
programmed, press and hold ENGINE
START/STOP for approximately
12 seconds to exit programming mode.
7. Return the key back into the transmitter.
Programming without Recognized
Transmitters
If two currently recognized transmitters are
not available, follow this procedure to
program up to eight transmitters. This
feature is not available in Canada. This
procedure will take approximately
30 minutes to complete. The vehicle must
be off and all transmitters to be
programmed must be with you. 1. Remove the vehicle key from the
transmitter.
2. Insert the vehicle key into the key lock cylinder on the driver door handle; then
turn the key counterclockwise, to the
unlock position, five times within
10 seconds.
The DIC displays REMOTE LEARN
PENDING, PLEASE WAIT.
3. Wait for 10 minutes until the DIC displays PRESS ENGINE START BUTTON TO
LEARN, then press ENGINE START/STOP.
The DIC will again display REMOTE LEARN
PENDING, PLEASE WAIT.
4. Repeat Step 3 two additional times. After the third time all previously known
transmitters will no longer work with the
vehicle. Remaining transmitters can be
relearned during the next steps.
The DIC should now display READY FOR
REMOTE # 1.
Transmitter Pocket without Bucket Seats
(Lower Compartment)
Transmitter Pocket with Bucket Seats

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
18 Keys, Doors, and Windows
5. Place the new transmitter in thetransmitter pocket/insert.
6. Press ENGINE START/STOP. When the transmitter is learned, the DIC display
will show that it is ready to program the
next transmitter.
7. Remove the transmitter from the transmitter pocket/insert and press
Kor
Qon the transmitter.
To program additional transmitters,
repeat Steps 5–7.
When all additional transmitters are
programmed, press and hold ENGINE
START/STOP for approximately
12 seconds to exit programming mode.
8. Return the key back into the transmitter.
Starting the Vehicle with a Low
Transmitter Battery
If the transmitter battery is weak or if there
is interference with the signal, the DIC may
display NO REMOTE DETECTED or NO
REMOTE KEY WAS DETECTED PLACE KEY IN
TRANSMITTER POCKET THEN START YOUR
VEHICLE when starting the vehicle. To start the vehicle:
Transmitter Pocket without Bucket Seats
(Lower Compartment)
Transmitter Pocket with Bucket Seats 1. Place the transmitter in the transmitter
pocket/insert.
2. With the vehicle in P (Park) or N (Neutral) press the brake pedal and ENGINE
START/STOP.
Replace the transmitter battery as soon
as possible.
Battery Replacement
{Warning
Never allow children to play with the RKE
transmitter. The transmitter contains a
small battery, which can be a choking
hazard. If swallowed, internal burns can
occur, resulting in severe injury or death.
Seek medical attention immediately if a
battery is swallowed.
{Warning
To avoid personal injury, do not touch
metal surfaces on the RKE transmitter
when it has been exposed to extreme
heat. These surfaces can be hot to the
touch at temperatures above 59 °C
(138 °F).

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
20 Keys, Doors, and Windows
Remote Vehicle Start
If equipped with the remote start feature,
the climate control system will come on
when the vehicle is started remotely,
depending on the outside temperature.
The rear defog and heated and ventilated
seats, if equipped, may also come on. See
Heated and Ventilated Front Seats052 and
Vehicle Personalization 0131.
If equipped, the automatic heated steering
wheel may also come on. See Heated
Steering Wheel 0100.
Laws in some communities may restrict the
use of remote starters. Check local
regulations for any requirements on remote
starting of vehicles.
Do not use remote start if the vehicle is low
on fuel. The vehicle may run out of fuel.
The vehicle cannot be remote started if:
.The RKE transmitter is inside the vehicle
or if the key is in the ignition.
.The hood is not closed.
.There is an emission control system
malfunction and the lamp is on.
.The ignition is in any mode other
than off.
.The hazard warning flashers are on.
.Two remote starts or a remote start with
an extension have been used.
.The vehicle is not in P (Park).
The engine will turn off during a remote
vehicle start if:
.The coolant temperature gets too high.
.The oil pressure gets low.
The RKE transmitter range may be reduced
while the vehicle is running.
Other conditions can affect the performance
of the transmitter. See Remote Keyless Entry
(RKE) System 010.
Starting the Engine Using Remote Start
1. Press and release
Q.
2. Immediately press and hold
/until the
turn signal lamps flash or for at least
four seconds.
When the vehicle starts, the parking
lamps will turn on. The doors will be
locked and the climate control system
may come on. The engine will continue to run for
15 minutes. After 30 seconds, repeat
Steps 1 and 2 for a 15-minute time
extension.
Turn the ignition on to operate the vehicle.
Extending Engine Run Time
The engine run time can be extended by
15 minutes, for a total of 30 minutes,
if during the first 15 minutes Steps 1 and 2
are repeated while the engine is still
running. An extension can be requested
30 seconds after starting.
A maximum of two remote starts, or a
single start with an extension, is allowed
between ignition cycles.
The vehicle's ignition must be turned on and
then back off to use remote start again.
Canceling a Remote Start
To cancel a remote start, do one of the
following:
.Press and hold/until the parking lamps
turn off.
.Turn on the hazard warning flashers.
.Turn the ignition on and then off.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
64 Seats and Restraints
Frontal airbags are designed to inflate in
moderate to severe frontal or near frontal
crashes to help reduce the potential for
severe injuries, mainly to the driver's or
front outboard passenger's head and chest.
Whether the frontal airbags will or should
inflate is not based primarily on how fast
the vehicle is traveling. It depends on what
is hit, the direction of the impact, and how
quickly the vehicle slows down.
Frontal airbags may inflate at different crash
speeds depending on whether the vehicle
hits an object straight on or at an angle,
and whether the object is fixed or moving,
rigid or deformable, narrow or wide.
Frontal airbags are not intended to inflate
during vehicle rollovers, rear impacts,
or many side impacts.
In addition, the vehicle has advanced
technology frontal airbags. Advanced
technology frontal airbags adjust the
restraint according to crash severity.
Seat-mounted side impact airbags are
designed to inflate in moderate to severe
side crashes depending on the location of
the impact. Seat-mounted side impact
airbags are not designed to inflate in frontal
impacts, near frontal impacts, rollovers,or rear impacts. A seat-mounted side impact
airbag is designed to inflate on the side of
the vehicle that is struck.
Roof-rail airbags are designed to inflate in
moderate to severe side crashes depending
on the location of the impact. In addition,
these roof-rail airbags are designed to inflate
during a rollover or in a severe frontal
impact. Roof-rail airbags are not designed to
inflate in rear impacts. Both roof-rail airbags
will inflate when either side of the vehicle is
struck or if the sensing system predicts that
the vehicle is about to roll over on its side,
or in a severe frontal impact.
In any particular crash, no one can say
whether an airbag should have inflated
simply because of the vehicle damage or
repair costs.
What Makes an Airbag Inflate?
In a deployment event, the sensing system
sends an electrical signal triggering a release
of gas from the inflator. Gas from the
inflator fills the airbag causing the bag to
break out of the cover. The inflator, the
airbag, and related hardware are all part of
the airbag module.
For airbag locations, see
Where Are the
Airbags? 062.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal
collisions, even belted occupants can contact
the steering wheel or the instrument panel.
In moderate to severe side collisions, even
belted occupants can contact the inside of
the vehicle.
Airbags supplement the protection provided
by seat belts by distributing the force of the
impact more evenly over the
occupant's body.
Rollover capable roof-rail airbags are
designed to help contain the head and chest
of occupants in the outboard seating
positions in the first and second rows. The
rollover capable roof-rail airbags are
designed to help reduce the risk of full or
partial ejection in rollover events, although
no system can prevent all such ejections.
But airbags would not help in many types
of collisions, primarily because the
occupant's motion is not toward those
airbags. See When Should an Airbag Inflate?
0 63.
Airbags should never be regarded as
anything more than a supplement to seat
belts.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
84 Seats and Restraints
Regular Cab Models1. For models without a rear seat, forward-facing child restraints should
only be installed in the right front
seating position with belts and a top
tether. See Securing Child Restraints
(With the Seat Belt in the Center Front
Seat) 092 or
Securing Child Restraints (With the Seat
Belt in the Rear Seat) 088 or
Securing Child Restraints (With the Seat
Belt in the Front Passenger Seat) 092.
If the child restraint manufacturer
recommends that the top tether be
attached, attach and tighten the top
tether to the top tether anchor, if your
vehicle has one. Refer to the child
restraint instructions and the following
steps:
1.1. Find the top tether anchor.
1.2. Route, attach, and tighten the top tether according to your child
restraint instructions and the
following instructions:
If the position you are using has an
adjustable head restraint and you
are using a dual tether, route the
tether around the head restraint.
If the position you are using has an
adjustable head restraint and you
are using a single tether, raise the
head restraint and route the tether
under the head restraint and in
between the head restraint posts. 2. Make sure the child restraint top tether
hook is completely closed and secured to
the top tether anchor.
3. Secure the child restraint in the right front seating position with the vehicle
belts. See Securing Child Restraints (With
the Seat Belt in the Center Front Seat)
0 92 or
Securing Child Restraints (With the Seat
Belt in the Rear Seat) 088 or
Securing Child Restraints (With the Seat
Belt in the Front Passenger Seat) 092.
4. Before placing a child in the child restraint, make sure it is securely held in
place. To check, grasp the child restraint
at the belt path and attempt to move it
side to side and back and forth. There
should be no more than 2.5 cm (1 in) of
movement for proper installation.
Double and Crew Cab Models 1. Attach and tighten the lower attachments to the lower anchors. If the
child restraint does not have lower
attachments or the desired seating
position does not have lower anchors,
secure the child restraint with the top
tether and the seat belt. Refer to the
child restraint manufacturer instructions
and the instructions in this manual.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 109
.Home
.Info App. This is where the selected Driver
Information Center (DIC) displays can be
viewed. See“Driver Information Center
(DIC) (Uplevel)” in the Index.
.Audio
.Navigation
.Phone
.Options
Home
Information displayed here can be
customized from the Options menu.
Speedometer : Displays how fast the vehicle
is moving in either kilometers per hour
(km/h) or miles per hour (mph).
Speed Sign : Shows sign information, which
comes from a roadway database in the
onboard navigation, if equipped.
Time : Displays the current time.
Fuel Range : Displays the approximate
distance the vehicle can be driven without
refueling. 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. Fuel
range cannot be reset. Audio
In the Audio menu, use the thumbwheel to
scroll through options, browse for music,
select from favorites, or change the audio
source. In the main view, scroll to change
the station or go to the next or previous
track.
Navigation
In the Navigation menu, if there is no active
route, a compass will be displayed. If there
is an active route, press the thumbwheel to
cancel or resume route guidance, mute or
unmute voice guidance, or access Recents or
Favorites.
Phone
In the Phone menu, if there is no active
phone call, view recent calls, scroll through
contacts, select from the favorites, or change
the phone source. If there is an active call,
mute the phone or switch to handset
operation.
Options
Use the thumbwheel to scroll through items
in the Options menu.
Head-up Display (HUD) :
If equipped, this
feature allows for adjusting the angle of the
HUD image and changing or turning off the
Speed Limit Sign.
HUD Rotation: Press the thumbwheel while
Adjust Rotation is highlighted to enter
Adjust Mode. Scroll to adjust the angle of
the HUD display. Press the thumbwheel to
confirm and save the setting. This feature
may only be available in P (Park).
Speed Limit Style: Press the thumbwheel
while Speed Limit Style is highlighted to
change the speed sign style or to turn it off.
Units : Press the thumbwheel while Units is
displayed to enter the Units menu. Choose
US or metric units by pressing the
thumbwheel while the desired item is
highlighted. A selected mark will be
displayed next to the selected item.
Info Page Options : Press the thumbwheel
while Info Page Options is displayed to
enter and select the items to be displayed
in the Info app. A selected mark will be
displayed next to the selected item.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 111
English Uplevel Shown, Midlevel and BaseLevel Similar
When the ignition is on, the fuel gauge
indicates about how much fuel is left in
the tank.
There is an arrow near the fuel gauge
pointing to the side of the vehicle the fuel
door is on.
When the indicator nears empty, the low
fuel light comes on. There still is a little fuel
left, but the vehicle should be refueled soon.
Here are three things that some owners ask
about. None of these show a problem with
the fuel gauge:
.It takes a little more, or less fuel to fill up
than the gauge indicated. For example,
the gauge may have indicated the tank
was half full, but it actually took a little
more, or less than half the tank's capacity
to fill the tank.
.The gauge moves a little while turning a
corner, speeding up or braking.
.The gauge takes a few seconds to
stabilize after the ignition is turned on
and goes back to empty when the
ignition is turned off.
Engine Oil Pressure Gauge
Uplevel Metric Shown, Base Level and Midlevel Similar
Uplevel English Shown, Base Level and
Midlevel 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

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 113
Voltmeter Gauge
Uplevel Shown, Base Level and MidlevelSimilar
When the ignition is on, this gauge indicates
the battery voltage.
When the engine is running, this gauge
shows the condition of the charging system.
The gauge can transition from a higher to
lower or a lower to higher reading. This is
normal. If the vehicle is operating outside
the normal operating range, the charging
system light comes on. See Charging System
Light 0115. The voltmeter gauge may also
read lower when in fuel economy mode.
This is normal. Readings outside the normal operating
range can also occur when a large number
of electrical accessories are operating in the
vehicle and the engine is left idling for an
extended period. This condition is normal
since the charging system is not able to
provide full power at engine idle. As engine
speeds are increased, this condition should
correct itself as higher engine speeds allow
the charging system to create maximum
power.
The vehicle can only be driven for a short
time with the readings outside the normal
operating range. If the vehicle must be
driven, turn off all accessories, such as the
radio and air conditioner.
Readings outside the normal operating
range indicate a possible problem in the
electrical system. Have the vehicle serviced
as soon as possible.
Seat Belt Reminders
Driver Seat Belt Reminder Light
There is a driver seat belt reminder light on
the instrument cluster.
When the vehicle is started, this light
flashes and a chime may come on to remind
the driver to fasten their seat belt.
Then the light stays on solid until the belt is
buckled. This cycle may continue several
times if the driver remains or becomes
unbuckled while the vehicle is moving.
If the driver seat belt is buckled, neither the
light nor the chime comes on.
Front Passenger Seat Belt Reminder
Light
The vehicle may have a front passenger seat
belt reminder light near the passenger
airbag status indicator. See
Passenger
Sensing System 066.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
116 Instruments and Controls
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.
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 Modifications0323.
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” underFilling the Tank (Pickup
Model) 0285 or
Filling the Tank (Chassis Cab Model) 0287. 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) 0283 or
Recommended Fuel (6.2L V8 Engine)
0 284.
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

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/6/20
Lighting 143
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.
Partially 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.The lever returns to its starting position
whenever it is released.
If after signaling a turn or a lane change the
arrows flash rapidly or do not come on, a
signal bulb could be burned out. If equipped
with LED turn signals, see your dealer.
Replace any burned out bulbs. If a bulb is
not burned out, check the fuse. See
Fuses
and Circuit Breakers 0353.
Turn Signal On Chime
If the turn signal is left on for more than
1.2 km (0.75 mi), a chime sounds at each
flash of the turn signal. A message may
appear in the Driver Information Center
(DIC). See Vehicle Messages 0130. To turn
the chime and message off, move the turn
signal lever to the off position.
Fog Lamps
If equipped, the fog lamp control is near the
exterior lamp control to the left of the
steering column.
The ignition must be on for the fog lamps
to come on.
#: Press to turn the fog lamps on or off.
A light will come on in the instrument
cluster.
When the fog lamps are turned on, the
parking lamps automatically turn on.
When the headlamps are changed to high
beam, the fog lamps also go off. When the
high-beam headlamps are turned off, the fog
lamps will come on again.