
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
224 Driving and Operating
Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the ENGINE START/STOP button for
more than five seconds will place the vehicle
in Service Mode. The instruments and audio
systems will operate as they do when the
vehicle is on, but the vehicle will not be able
to be driven. The engine will not start in
Service Mode. Press the ENGINE START/STOP
button again to turn the vehicle off.
Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
SeeAdd-On Electrical Equipment 0338. Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. The remote key must be in the vehicle.
Press ENGINE START/STOP with the brake
pedal applied. When the engine begins
cranking, let go of the button.
The driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts. When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), press ENGINE START/STOP
to continue engine cranking.
Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position immediately after
cranking has ended, can overheat and
damage the cranking motor, and drain
the battery. Wait at least 15 seconds
between each try, to let the cranking
motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try
pushing the accelerator pedal all the way
to the floor and holding it there while
pressing ENGINE START/STOP for up to a
maximum of 15 seconds. Wait at least
15 seconds between each try, to allow
the cranking motor to cool down. When
the engine starts, let go of the button
and accelerator. If the vehicle starts
briefly but then stops again, do the
same thing. This clears the extra gasoline

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 245
Once the 4x4 shift has completed, the DIC
message disappears, the 4x4 graphic stops
flashing, and the current setting is indicated.
The actual 4x4 shift request is only made
after the button is released. The 4x4 graphic
will remain flashing until the shift request
has completed.
A DIC message displays. Once the 4x4 shift
has completed, the DIC message disappears,
the 4x4 graphic stops flashing, and the
current setting is indicated.
Brakes
Electric Brake Boost
Vehicles equipped with electric brake boost
have hydraulic brake circuits that are
electronically controlled when the brake
pedal is applied during normal operation.
The system performs routine tests and turns
off within a few minutes after the vehicle is
turned off. Noise may be heard during this
time. If the brake pedal is pressed during
the tests or when the electric brake boost
system is off, a noticeable change in pedal
force and travel may be felt. This is normal.
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
ABS performs a system check when the
vehicle is first driven. A momentary motor
or clicking noise may be heard while this
test is going on, and the brake pedal may
move slightly. This is normal.
If there is a problem with ABS, this warning
light stays on. SeeAntilock Brake System
(ABS) Warning Light 0122.
ABS does not change the time needed to
get a foot on the brake pedal and does not
always decrease stopping distance. If you
get too close to the vehicle ahead, there will
not be enough time to apply the brakes if
that vehicle suddenly slows or stops. Always
leave enough room ahead to stop, even
with ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down firmly. Hearing or feeling ABS
operate is normal.
Braking in Emergencies
ABS allows steering and braking at the same
time. In many emergencies, steering can
help even more than braking.
Electric Parking Brake
Work Truck Shown, Others Similar
The Electric Parking Brake (EPB) can always
be applied, even if the vehicle is off. In case
of insufficient electrical power, the EPB

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 257
path, ACC works like regular cruise control.
ACC uses a windshield mounted front
camera sensor.
If equipped with Super Cruise, ACC uses a
radar sensor(s) as well to detect other
vehicles. SeeRadio Frequency Statement
0 450.
If a vehicle is detected in your path, ACC can
apply acceleration or limited, moderate
braking to maintain the selected following
gap. To disengage ACC, apply the brake.
If ACC is controlling the vehicle speed when
the Traction Control System (TCS) or
StabiliTrak/Electronic Stability Control (ESC)
system activates, ACC may automatically
disengage. See Traction Control/Electronic
Stability Control 0247. When road
conditions allow ACC to be safely used, ACC
can be turned back on. Disabling the TCS or
StabiliTrak/ESC system will disengage and
prevent engagement of ACC.
ACC can reduce the need for you to
frequently brake and accelerate, especially
when used on expressways, freeways, and
interstate highways. When used on other
roads, you may need to take over the
control of braking or acceleration more
often.{Warning
ACC has limited braking ability and may
not have time to slow the vehicle down
enough to avoid a collision with another
vehicle you are following. This can occur
when vehicles suddenly slow or stop
ahead, or enter your lane. Also see
“Alerting the Driver” later in this section.
Complete attention is always required
while driving and you should be ready to
take action and apply the brakes. See
Defensive Driving 0206.
{Warning
ACC will not detect or brake for children,
pedestrians, animals, or other objects.
Do not use ACC when:
.On winding and hilly roads or when
the camera sensor is blocked by snow,
ice, or dirt. The system may not
detect a vehicle ahead. Keep the
windshield and headlamps clean.
.When visibility is poor due to rain,
snow, fog, dirt, insect residue, or dust;
when other foreign objects obscure
(Continued)
Warning (Continued)
the camera’s view; or when the
vehicle in front or oncoming traffic
causes additional environmental
obstructions, such as road spray. ACC
performance is limited under these
conditions.
.On slippery roads where fast changes
in tire traction can cause excessive
wheel slip
.With extremely heavy cargo loaded in
the cargo area or rear seat
.When towing a trailer

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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260 Driving and Operating
.If ACC is holding the vehicle at a stop and
there is another vehicle directly ahead,
pressing RES+ will increase the set speed.
.Pressing RES+ when there is no longer a
vehicle ahead or the vehicle ahead is
pulling away and the brake is not applied
with cause the ACC to resume.
When it is determined that there is no
vehicle ahead or the vehicle ahead is beyond
the selected following gap, then the vehicle
speed will increase to the set speed.
Reducing Speed While ACC Is at a Set Speed
If ACC is already activated, do one of the
following:
.Use the brake to get to the desired lower
speed. Release the brake and press SET–.
The vehicle will now cruise at the lower
speed.
.Press and hold SET– until the desired
lower speed is reached, then release it.
.To decrease the vehicle speed in smaller
increments, press SET− briefly. For each
press, the vehicle goes about 1 km/h
(1 mph) slower.
.To decrease the vehicle speed in larger
increments, hold SET−. While holding SET
−, the vehicle speed decreases to the next
5 km/h (5 mph) step, then continues to
decrease by 5 km/h (5 mph) at a time.
The set speed can also be decreased while
the vehicle is stopped.
.If stopped with the brake applied, press
or hold SET− until the desired set speed is
displayed.
Selecting the Follow Distance Gap
When a slower moving vehicle is detected
ahead within the selected following gap,
ACC will adjust the vehicle's speed and
attempt to maintain the follow distance gap
selected.
Press
[on the steering wheel to adjust
the following gap. Each press cycles the gap
button through three settings: Far, Medium,
or Near.
When pressed, the current gap setting
displays briefly on the instrument cluster
and HUD, if equipped. The gap setting will
be maintained until it is changed.
Far Gap Setting
Medium Gap Setting

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 261
Near Gap Setting
If equipped, and a trailer is electrically
connected, the gap setting display will be as
follows:
Far Gap Setting with Trailer
Medium Gap Setting with Trailer
Near Gap Setting with Trailer
Since each gap setting corresponds to a
following time (Far, Medium, or Near), the
following distance will vary based on vehicle
speed. The faster the vehicle speed, the
further back your vehicle will follow a
vehicle detected ahead. Consider traffic and
weather conditions when selecting the following gap. The range of selectable gaps
may not be appropriate for all drivers and
driving conditions.
Changing the gap setting automatically
changes the alert timing sensitivity (Far,
Medium, or Near) for the Forward Collision
Alert (FCA) feature. See
Forward Collision
Alert (FCA) System 0293.
Courtesy Gap (if equipped with Super Cruise)
Press and hold
[on the steering wheel
when vehicle is moving to temporarily
increase the gap with the vehicle ahead to
allow for merging traffic.
Press and hold
[when stopped to cancel
ACC from resuming automatically (if the
stop is brief) and remain stationary. This can
be used to allow traffic to merge between
you and the vehicle ahead. Press RES+ or
the accelerator pedal to resume ACC.
Following distance gap will return to the
original selection after hold.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
262 Driving and Operating
Alerting the Driver
With Head-Up Display
Without Head-Up Display
If ACC is engaged, driver action may be
required when ACC cannot apply sufficient
braking because of approaching a vehicle
too rapidly.
When this condition occurs, the collision
alert symbol will flash on the windshield.
Either eight beeps will sound from the front,
or both sides of the Safety Alert Seat,
if equipped, will pulse five times. See
“Collision/Detection Systems” underVehicle
Personalization 0137.
See Defensive Driving 0206. Approaching and Following a Vehicle
The vehicle ahead indicator is in the
instrument cluster and HUD (if equipped).
It only displays when a vehicle is detected
in your vehicle’s path moving in the same
direction. If this symbol is not displaying,
ACC will not respond to or brake for vehicles
ahead.
ACC automatically slows the vehicle down
and adjusts vehicle speed to follow a
detected vehicle ahead at the selected
following gap. The vehicle speed increases or
decreases to follow a detected vehicle in
front of your vehicle when that vehicle is
traveling slower than your vehicle set speed.
It may apply limited braking, if necessary.
When braking is active, the brake lamps will
come on. The automatic braking may feel or
sound different than if the brakes were
applied manually. This is normal.
Passing a Vehicle While Using ACC
If the set speed is high enough, and the left
turn signal is used to pass a vehicle ahead
in the selected following gap, ACC may
assist by gradually accelerating the vehicle
prior to the lane change.{Warning
When using ACC to pass a vehicle or
perform a lane change, the following
distance to the vehicle being passed may
be reduced. ACC may not apply sufficient
acceleration or braking when passing a
vehicle or performing a lane change.
Always be ready to manually accelerate
or brake to complete the pass or lane
change.
Stationary or Very Slow-Moving Objects
{Warning
ACC may not detect and react to stopped
or slow-moving vehicles ahead of you. For
example, the system may not brake for a
vehicle it has never detected moving. This
can occur in stop-and-go traffic or when a
vehicle suddenly appears due to a vehicle (Continued)

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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268 Driving and Operating
this section and the ACC section before
using Super Cruise. SeeAdaptive Cruise
Control (Camera) 0256.
An active Connected Service plan that
includes Super Cruise Services is required to
use Super Cruise.
{Warning
Super Cruise does not perform all aspects
of driving, nor does it do everything a
driver can do. Super Cruise only steers to
maintain vehicle position in the current
lane or, under some circumstances, to
change lanes. Super Cruise can only be
used with Adaptive Cruise Control.
Super Cruise does:
.Not prevent crashes or warn of
possible crashes.
.Not steer to avoid stopped or
slow-moving vehicles, cross-traffic,
construction barriers or cones,
motorcycles, children, pedestrians,
animals, or other objects on the road.
.Not steer in response to vehicles or
objects next to your vehicle, including
vehicles attempting to enter your lane. (Continued)
Warning (Continued)
.Not respond to traffic lights, stop
signs, or other traffic control devices.
.Not respond to crossing traffic.
.Not make turns.
.Not steer to merge onto or to exit
highways.
.Not steer to avoid, or steer through
construction zones.
.Not function on surface streets.
.Not respond to oncoming traffic.
.Not function in city driving conditions.
{Warning
Some state and local laws may require
hands to be kept on the steering wheel
at all times. Only remove your hands
from the steering wheel if Super Cruise is
engaged, it is safe to do so, and it is
permitted by state and local laws.
{Warning
Failure to supervise the driving task and
to respond appropriately, even while
Super Cruise is operating, can cause a
crash. Super Cruise may not respond as
you would to all driving situations and
may not maintain lane position under all
conditions.
It is extremely important to pay
attention to the operation of the vehicle,
even while using Super Cruise. Do not
use a hand-held device while driving,
even with Super Cruise engaged. To
prevent serious injury or death:
.Always remain properly seated in the
driver seat with your seat belt
fastened.
.Never remove your hands from the
steering wheel when Super Cruise is
not operating.
.Always make sure traffic conditions
are safe before using Super Cruise.
.Always keep the entire vehicle and the
sensors clean. Sensors are on the
front, sides, and rear of the vehicle.(Continued)

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 271
When the steering wheel is moved
manually, the steering wheel light bar
flashes blue and
^on the instrument
cluster turns blue to indicate Super Cruise is
not steering the vehicle.
When ready to allow Super Cruise to
resume steering again, position the vehicle
in the center of the lane, hold the steering
wheel until the steering wheel light bar
turns green, and then release the steering
wheel when it is safe to do so.
{Warning
To help prevent crashes before making a
lane change:
.Always check mirrors.
.Glance over your shoulder.
.Use the turn signals.
Super Cruise Lane Change
Super Cruise can steer to perform a single
lane change under certain conditions when
requested by the driver or initiated by the
Super Cruise System. To request a lane change:
1. Verify the lane next to your vehicle is clear and conditions are safe to make a
lane change.
2. Use the turn signal lever to activate the turn signal in the direction of the desired
lane change.
3. Return the turn signal lever to the neutral position after the lane change.
See Turn and Lane-Change Signals 0149.
Super Cruise System may initiate a single
lane change when enabled through Vehicle
Personalization under following conditions:
.The Super Cruise System may initiate a
lane change to the left to pass a slower
moving vehicle ahead and a subsequent
lane change to right to return to your
original lane.
.Super Cruise System may initiate a lane
change to left or right when current lane
is ending ahead.
.To cancel a Super Cruise lane change,
return the turn signal lever to the neutral
position or move the turn signal lever.
.Super Cruise steering can be overridden
with manual steering at any time to
cancel a Super Cruise lane change.
If Super Cruise detects that traffic is clear,
Super Cruise will steer the vehicle to
perform the lane change. A message appears
on the Driver Information Center (DIC)
during the lane change to provide more
information on the status of the lane
change.
Super Cruise Lane Change functionality is
only available on Super Cruise capable
divided roads.
The Super Cruise Lane Change feature can
be enabled or disabled through the vehicle
personalization menu. See “Super Cruise
Lane Change” underVehicle Personalization
0 137.
Super Cruise Lane Change may be disabled
when a trailer or other accessory (e.g. bike
rack, cargo tray, etc) is detected.
Do not use Super Cruise Lane Change
feature when towing a trailer.