brake GMC SIERRA DENALI 2019 Service Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 235If equipped, the Stop/Start system
will become unavailable when Tow/
Haul Mode is active.
Tow/Haul Mode Grade Braking Tow/Haul Mode Grade Braking is
only enabled while the Tow/Haul
Mode is selected and the vehicle is
not in the Range Selection Mode.
See Manual Mode 0 232 . Tow/Haul
Mode Grade Braking assists in
maintaining desired vehicle speeds
when driving on downhill grades by
using the engine and transmission
to slow the vehicle.
See Towing Equipment 0 285 .Drive Systems Four-Wheel Drive If equipped, four-wheel drive
engages the front axle for extra
traction.
Read the appropriate section for
transfer case operation before
using.
CautionDo not drive on clean, dry
pavement in 4
m and 4
n (if
equipped) for an extended period
of time. These conditions may
cause premature wear on the
vehicle ’ s powertrain.
Driving on clean, dry pavement in 4
m or 4
n may:
.
Cause a vibration to be felt in
the steering system.
.
Cause tires to wear faster.{ WarningIf equipped with four-wheel drive,
the vehicle will be free to roll if the
transfer case is in N (Neutral),
even when the shift lever is in
P (Park). You or someone else
could be seriously injured. Be
sure the transfer case is in a drive
gear — 2
m , 4
m , or 4
n — or set the
parking brake before placing the
transfer case in N (Neutral). See
Shifting Into Park 0 225 .
Caution
Extended high-speed operation in
4
n may damage or shorten the
life of the drivetrain.
An engagement noise and bump is
normal when shifting between 4
n and 4
m or N (Neutral), with the
engine running.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 237The 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
to indicate that the 4x4 transfer case
has been requested to shift to the
new desired state.
Once the 4x4 shift has completed,
the DIC message disappears, the
4x4 graphic stops flashing, and the
current setting is indicated.
When a shift to 2
m is completed
successfully while in P (park), the
parking brake will engage. To
resume driving, shift the
transmission to the desired gear
and manually release the parking
brake or press the accelerator pedal
to begin driving. See Electric
Parking Brake 0 241 .
If equipped, use 4
n , AUTO, or 4
m to
provide additional traction when
parking on a steep grade with poor
traction such as ice, snow, mud,
or gravel. Shifting Into 4
n 1. The ignition must be on and
the vehicle must be stopped or
moving less than 5 km/h
(3 mph) with the transmission
in N (Neutral). It is best for the
vehicle to be moving
1.6 to 3.2 km/h (1 to 2 mph).
2. Press 4
n . 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 to indicate that the 4x4
transfer case has been
requested to shift to the new
desired state.
Once the 4x4 shift has
completed, the DIC message
disappears, the 4x4 graphic
stops flashing and the current
setting is indicated.
If vehicle speed is higher when shift
request occurs, a DIC message
displays. Reduce vehicle speed. If transmission is not in N (Neutral)
when shift request occurs, a DIC
message displays. The vehicle will
allow 20 seconds for the shift to
occur. After this time, a graphic in
the instrument cluster will indicate
that the transfer case is in 4
n .
CautionShifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
If the transmission is not shifted into
N (Neutral) or the vehicle has not
slowed to 5 km/h (3 mph) within
20 seconds, the transfer case will
remain in its original state. This will
be indicated in the instrument
cluster.
With the vehicle moving less than
5 km/h (3 mph) and the transmission
in N (Neutral), attempt the shift
again.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
238 Driving and Operating Shifting Out of 4
n1. The vehicle must be
stopped or moving less than
5 km/h (3 mph) with the
transmission in N (Neutral) and
the ignition on. It is best for the
vehicle to be moving
1.6 to 3.2 km/h (1 to 2 mph).
2. Press 4
m , AUTO or 2
m . 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 to indicate
the state of the request.
Once the 4x4 shift has
completed, the DIC message
disappears, the 4x4 graphic
stops flashing, and the current
setting is indicated.
If vehicle speed is higher when
shift request occurs, a DIC
message displays. Reduce
vehicle speed. If transmission is not in N (Neutral)
when shift request occurs, DIC
messages will display. The vehicle
will allow 20 seconds for this shift to
occur. After this time, a graphic in
the instrument cluster will indicate
that the transfer case is in 4
n .
CautionShifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
If the transmission is not shifted into
N (Neutral) or the vehicle has not
slowed to 5 km/h (3 mph) within
20 seconds, the transfer case will
remain in its original state. This will
be indicated in the instrument
cluster.
With the vehicle moving less than
5 km/h (3 mph), and the
transmission in N (Neutral), attempt
the shift again. Shifting Into N (Neutral)
To shift into N (Neutral):
1. Start the vehicle.
2. Shift the transmission to
N (Neutral).
3. Shift the transfer case to 2
m .
4. Apply the park brake and/or
service brake.
5. Press 2
m five times in
10 seconds until the N (Neutral)
graphic starts flashing in the
instrument cluster. When the
shift is complete, the graphic
stops flashing. If the park brake
and/or service brake is not
applied within 20 seconds, the
transfer case will remain in the
original state.
6. If the transmission is not
shifted into N (Neutral) or the
vehicle has not slowed to
5 km/h (3 mph) within
20 seconds, the transfer case
will remain in its original state.
This will be indicated in the
instrument cluster.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 239Shifting Out of N (Neutral)
To shift out of N (Neutral):
1. Turn the ignition on with engine
off.
See Ignition Positions (Key
Access) 0 217 or Ignition
Positions (Keyless Access)
0 219 .
2. Set the Parking Brake. See
Electric Parking Brake 0 241 .
3. Shift the transmission to
N (Neutral)
4. Shift the transfer case to 2
m .
Transfer case shifts out of
N (Neutral) can only be made
when the transfer case is in 2
m . When the shift to 2
m is
complete, the graphic in the
instrument cluster will stop
flashing. If the transfer case
cannot complete a shift, the
graphic will return to the
previously selected setting. Single Speed Transfer Case
If equipped, the transfer case
controls are used to shift into and
out of four-wheel drive.
To shift the transfer case, press the
desired button. The graphic in the
instrument cluster will flash while a
shift is in progress. The graphic
displayed will change to indicate the
setting requested
When the shift is complete the
graphic will stop flashing. The DIC
message turns off once the shift is
complete. If the transfer case can
not complete a shift request, it will
go back to its last chosen setting. The settings are:
2
m (Two-Wheel Drive High) : Use
for driving on most streets and
highways. The front axle is not
engaged. This setting provides the
best fuel economy.
4
m (Four-Wheel Drive High) : Use
this setting when extra traction is
needed, such as when driving on
snowy or icy roads, when
off-roading, or when plowing snow.
AUTO (Automatic Four-Wheel
Drive)
Use when road surface conditions
are variable. When driving in AUTO,
the front axle is engaged, and the
vehicle's power is sent to the front
and rear wheels automatically
based on driving conditions. This
setting provides slightly lower fuel
economy than 2
m .
Shifts between 2
m , 4
m and AUTO
Any of these shifts can be made at
normal driving speed.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
240 Driving and Operating 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.
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 Antilock Brake
System (ABS) This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
0 152 .
If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel. ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear noise or
feel vibration while the ABS is
operating.
The Traction Control System (TCS)/
StabiliTrak indicator light will flash to
indicate that ABS is active. When

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 241ABS is active, it may indicate that
road surfaces are slippery. Braking
sooner may be required for driving
conditions.
Braking in Emergencies ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Electric Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is off. To prevent draining the battery,
avoid repeated cycles of the EPB
when the engine is not running.
The system has a
Y or PARK
Electric Parking Brake light, and a
8Service Parking Brake light.
See Electric Parking Brake Light
0 152 and Service Electric Parking
Brake Light 0 152 . There are also
parking brake-related Driver
Information Center (DIC) messages.
Before leaving the vehicle, check for
the
Y or PARK light to ensure that
the parking brake is applied.
EPB Apply To apply the EPB:
1. Be sure the vehicle is at a
complete stop.
2. Press the EPB switch
momentarily.
The
Y or PARK light will flash and
then stay on once the EPB is fully
applied. If the
Y or PARK light
flashes continuously, then the EPB
is only partially applied or there is a problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the
light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the
Y or
PARK light is flashing. See your
dealer. See Electric Parking Brake
Light 0 152 .
If the
8 light is on, press the EPB
switch and hold it. Continue to hold
the switch until the
Y or PARK
light remains on. If the
8 light
remains on, see your dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
pressed. If the switch is pressed
until the vehicle comes to a stop,
the EPB will remain applied.
The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is
normal, and is done to periodically
check the correct operation of the
EPB system.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
242 Driving and Operating If the EPB fails to apply, block the
rear wheels to prevent vehicle
movement.
EPB Release To release the EPB:
1. Turn the ignition on or to ACC/
ACCESSORY.
2. Apply and hold the brake
pedal.
3. Press the EPB switch
momentarily.
The EPB is released when the
Yor PARK light is off.
If the
8 light is on, release the EPB
by pressing and holding the EPB
switch. Continue to hold the switch
until the
Y or PARK light is off.
If either light stays on after release
is attempted, see your dealer. CautionDriving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
Automatic EPB Release The EPB will automatically release if
the vehicle is running, placed into
gear, and an attempt is made to
drive away. Avoid rapid acceleration
when the EPB is applied, to
preserve parking brake lining life.
Brake Assist The Brake Assist feature assists in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
Electronic Brake Control Module
(EBCM) which controls the hydraulic
brake circuits to detect when the
driver has quickly and forcefully applied the brake pedal in an
attempt to quickly stop or slow down
the vehicle and to provide additional
braking beyond a normal brake
pedal apply. Minor noise during this
time is normal and the brake pedal
should be applied as the driving
dictates. The Brake Assist feature
will automatically disengage when
the brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
{ WarningDo not rely on the HSA feature.
HSA does not replace the need to
pay attention and drive safely.
You may not hear or feel alerts or
warnings provided by this system.
Failure to use proper care when
driving may result in injury, death,
or vehicle damage. See
Defensive Driving 0 198 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 243This feature is designed to prevent
the vehicle from rolling, either
forward or rearward, during vehicle
drive off. HSA will be automatically
activated after the vehicle has come
to a complete standstill on a grade.
During the transition period between
when the brake pedal is released
and the accelerator pedal is
pressed, HSA holds the braking
pressure to ensure that there is no
rolling. The brakes will automatically
release when the accelerator pedal
is applied. It will not activate if the
vehicle is in a drive gear and facing
downhill, or if the vehicle is facing
uphill and in R (Reverse). Ride Control Systems Traction Control/
Electronic Stability
Control System Operation The vehicle has a Traction Control
System (TCS) and StabiliTrak/
Electronic Stability Control (ESC),
an electronic stability control
system. These systems help limit
wheel spin and assist the driver in
maintaining control, especially on
slippery road conditions.
TCS activates if it senses any of the
drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak/ESC activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak/ESC selectively applies
braking pressure to any one of the
vehicle wheel brakes to assist the driver in keeping the vehicle on the
intended path. Trailer Sway Control
(TSC) is also on automatically when
the vehicle is started. See Trailer
Sway Control (TSC) 0 293 .
If cruise control is being used and
traction control or StabiliTrak/ESC
begins to limit wheel spin, cruise
control will disengage. Cruise
control may be turned back on when
road conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See If the Vehicle Is Stuck 0 208
and “ Turning the Systems Off and
On ” later in this section.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
244 Driving and Operating When the transfer case (if equipped)
is in Four-Wheel Drive Low, the
stability system is automatically
disabled,
g comes on, and the
appropriate message will appear on
the Driver Information Center (DIC).
Both traction control and StabiliTrak/
ESC are automatically disabled in
this condition.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin.
.
Flash when StabiliTrak/ESC is
activated.
.
Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and d comes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
d comes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait
15 seconds.
3. Start the engine.
Drive the vehicle. If
d comes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.
Turning the Systems Off
and On The button for TCS and StabiliTrak/
ESC is on the center stack.
CautionDo not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release
g . The traction off light
idisplays in the instrument cluster.
The appropriate message will
display in the DIC. To turn TCS on
again, press and release
g . The
traction off light
i displayed in the
instrument cluster will turn off.
If TCS is limiting wheel spin when
gis pressed, the system will not turn
off until the wheels stop spinning.
To turn off both TCS and StabiliTrak/
ESC, press and hold
g until the
traction off light
i and the
StabiliTrak/ESC OFF light
g come
on and stay on in the instrument

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 245cluster, then release. The
appropriate message will display in
the DIC.
To turn TCS and StabiliTrak/ESC on
again, press and release
g . The
traction off light
i and the
StabiliTrak/ESC OFF light
g in the
instrument cluster turn off.
StabiliTrak/ESC will automatically
turn on if the vehicle exceeds
56 km/h (35 mph). Traction control
will remain off.
The vehicle has a Trailer Sway
Control (TSC) feature and a Hill
Start Assist (HSA) feature.
See Trailer Sway Control (TSC)
0 293 or Hill Start Assist (HSA)
0 242 .
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications
0 313 . Hill Descent
Control (HDC) If equipped, Hill Descent Control
(HDC) sets and maintains vehicle
speed while driving down steep
grades in a forward or reverse gear.
The HDC switch is on the center
stack, below the climate controls.
Press
5 to enable or disable HDC.
Vehicle speed must be below
50 km/h (31 mph).
When enabled, the HDC light
displays on the instrument cluster.
A blinking HDC light indicates the
system is actively applying the
brakes to maintain vehicle speed.
HDC can maintain vehicle speeds
between 1 and 22 km/h (1 and
14 mph) on grades greater than or
equal to 10%. If HDC is to be used for more than
three minutes or on grades steeper
than 25%, the transfer case should
be put into Four-Wheel Drive Low
(4
n ) to reduce the possibility of
brake overheating.
Noise from the Electronic Brake
Control Module (EBCM) is normal
when HDC is active.
When HDC is activated, the initial
HDC speed is set to the current
driving speed. It can be increased or
decreased by pressing +RES or
SET- on the steering wheel, or by
applying the accelerator or brake
pedal. This adjusted speed
becomes the new set speed.
HDC will remain enabled between
30 and 60 km/h (19 and 37 mph);
however, vehicle speed cannot be
set or maintained in this range. HDC
will automatically disable if the
vehicle speed is above 80 km/h
(50 mph) or above 60 km/h
(37 mph) for at least 30 seconds.
5 must be pressed again to
re-enable HDC. HDC may disable
after an extended period of use.