brake light GMC YUKON DENALI 2015 Owner's Manual

Black plate (39,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Driving and Operating 9-39
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 vehiclesuddenly 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 the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
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.
Parking Brake
Set the parking brake by holding the
regular brake pedal down, then
pushing down the parking brake
pedal.
If the ignition is on, the brake
system warning light will come on.
See
Brake System Warning Light on
page 5-23.

Black plate (40,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-40 Driving and Operating
{Caution
Driving 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.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will flash and a
chime will sound warning you that
the parking brake is still on. If you are towing a trailer and are
parking on a hill, see
Driving
Characteristics and Towing Tips on
page 9-70.
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates. Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation 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)
Vehicles with StabiliTrak have an
HSA feature, which may be useful
when the vehicle is stopped on a
grade. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After the driver
completely stops and holds the
vehicle in a complete standstill on a
grade, HSA will be automatically

Black plate (42,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-42 Driving and Operating
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.
SeeIf the Vehicle Is Stuck on
page 9-13 and“Turning the
Systems Off and On” later in this
section.
When the transfer case is in
Four-Wheel Drive Low, the stability
system is automatically disabled,
the StabiliTrak OFF light comes on,
and the appropriate message will
appear on the DIC. Both traction
control and StabiliTrak 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 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
dcomes 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
dcomes 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
dcomes 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
is on the instrument panel to the left
of the steering wheel.
{Caution
Do not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.

Black plate (44,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-44 Driving and Operating
Locking Rear Axle
Vehicles with a locking rear axle can
give more traction on snow, mud,
ice, sand, or gravel. It works like a
standard axle most of the time, but
when traction is low, this feature will
allow the rear wheel with the most
traction to move the vehicle.
Automatic Level Control
The automatic level control rear
suspension is available on light-duty
vehicles and comes as a part of the
MagneRide suspension, if equipped.
Automatic Level Control (ALC) may
also be available as a stand alone
feature.This type of level control is fully
automatic and will provide a better
leveled riding position as well as
better handling under a variety of
passenger and loading conditions.
An air compressor connected to the
rear shocks will raise or lower the
rear of the vehicle to maintain
proper vehicle height. The system is
activated when the ignition key is
turned to ON/RUN and will
automatically adjust vehicle height
thereafter. The system may exhaust
(lower vehicle height) for up to
10 minutes after the ignition key has
been turned off. You may hear the
air compressor operating when the
height is being adjusted.
If a weight-distributing hitch is being
used, it is recommended to allow
the shocks to inflate, thereby
leveling the vehicle prior to adjusting
the hitch.
Cruise Control
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.
With cruise control a speed of about
40 km/h (25 mph) or more can be
maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
If the brakes are applied, the cruise
control disengages.

Black plate (47,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Driving and Operating 9-47
Using Cruise Control on Hills
How well the cruise control works
on hills depends on the vehicle
speed, the load, and the steepness
of the hills. When going up steep
hills, pressing the accelerator pedal
may be necessary to maintain
vehicle speed. When going
downhill, Cruise Grade Braking
helps maintain the driver selected
speed.
Cruise Grade Braking is enabled
when the vehicle is started and
cruise control is active. It is not
enabled in Range Selection Mode.
It assists in maintaining driver
selected speed when driving on
downhill grades by using the engine
and transmission to slow the
vehicle.
To disable and enable Cruise Grade
Braking for the current ignition key
cycle, press and hold the Tow/Haul
button for three seconds. A DIC
message displays. See
Transmission Messages on
page 5-47.For other forms of Grade Braking,
see
Automatic Transmission on
page 9-29 andTow/Haul Mode on
page 9-34.
Ending Cruise Control
There are four ways to end cruise
control:
.Step lightly on the brake pedal.
.Press*.
.Shift the transmission to
N (Neutral).
.To turn off cruise control,
press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if the
5button
is pressed or the ignition is
turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows the driver to
select the cruise control set speed and following gap. Read this entire
section before using this system.
The following gap is the following
time between your vehicle and a
vehicle detected directly ahead in
your path, moving in the same
direction. If no vehicle is detected in
your path, ACC works like regular
cruise control. ACC uses a radar
sensor. See
Radio Frequency
Statement on page 13-12.
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 your vehicle
speed when the traction control
system (TCS) or electronic stability
control system activates, the ACC
may automatically disengage. See
Traction Control/Electronic Stability
Control on page 9-41. When road
conditions allow ACC to be safely
used, the ACC can be turned
back on.

Black plate (51,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Driving and Operating 9-51
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. SeeForward
Collision Alert (FCA) System on
page 9-58.
Alerting the Driver
Without Head-Up Display
With 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, six red
lights or the collision alert symbol on
the HUD, if equipped, will flash on
the windshield, and either eight
beeps will sound from the front,
or both sides of the Safety Alert
Seat will pulse five times. See
“Collision/Detection Systems”
under
Vehicle Personalization on
page 5-50.
See Defensive Driving on page 9-3.
Approaching and Following a
VehicleThe vehicle ahead symbol is in the
instrument cluster and HUD,
if equipped. The vehicle ahead symbol 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 to
vehicles ahead.
ACC automatically slows the vehicle
down and adjusts vehicle speed to
follow the vehicle in front at the
selected follow gap. The vehicle
speed increases or decreases to
follow the vehicle in front of you, but
will not exceed the set speed. It may
apply limited braking, if necessary.
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.

Black plate (54,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-54 Driving and Operating
Do Not Use ACC on Hills and
When Towing a Trailer
Do not use ACC when driving on
steep hills or when towing a trailer.
ACC will not detect a vehicle in the
lane while driving on steep hills. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.Disengaging ACC
There are three ways to
disengage ACC:
.Step lightly on the brake pedal.
.Press*.
.Press5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or if the ignition is turned off.
Cleaning the Sensing System
The radar sensor on the front of the
vehicle can become blocked by
snow, ice, dirt, or mud. This area
needs to be cleaned for ACC to
operate properly.
For cleaning instructions, see
“Washing the Vehicle” under
Exterior Care on page 10-81.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.
Driver Assistance
Systems
This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{Warning
Do not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
on page 9-3.
(Continued)

Black plate (58,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-58 Driving and Operating
parking assist to work properly with
a small item attached to the trailer
hitch. Turn off parking assist when
towing a trailer.
To turn the rear parking assist
symbols, guidance lines, or Rear
Cross Traffic Alert on or off, see
“Rear Camera”underVehicle
Personalization on page 5-50
Assistance Systems for
Driving
If equipped, when driving the
vehicle forward, Forward Collision
Alert (FCA), Lane Departure
Warning (LDW), Side Blind Zone
Alert (SBZA), Lane Change Alert
(LCA), and/or the Active Emergency
Braking System can help to avoid a
crash or reduce crash damage.
Forward Collision Alert
(FCA) System
If equipped, the FCA system may
help to avoid or reduce the harm
caused by front-end crashes. When approaching a vehicle ahead too
quickly, FCA provides a red flashing
alert on the windshield and rapidly
beeps or pulses the driver seat.
FCA also lights an amber visual
alert if following another vehicle
much too closely.
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 40 km/h (25 mph). If the
vehicle has Adaptive Cruise Control
(ACC), it can detect vehicles to
distances of approximately 110 m
(360 ft) and operates at all speeds.
See
Adaptive Cruise Control on
page 9-47.
{Warning
FCA is a warning system and
does not apply the brakes. When
approaching a slower-moving or
stopped vehicle ahead too rapidly,
or when following a vehicle too
closely, FCA may not provide a
(Continued)
Warning (Continued)
warning with enough time to help
avoid a crash. FCA does not warn
of pedestrians, animals, signs,
guardrails, bridges, construction
barrels, or other objects. Be ready
to take action and apply the
brakes. For more information, see
Defensive Driving on page 9-3.
FCA can be disabled with the FCA
steering wheel control, or if your
vehicle is equipped with Adaptive
Cruise Control (ACC), through
vehicle personalization. See the
“Auto Collision Preparation” portion
of “Collision/Detection Systems”
under Vehicle Personalization on
page 5-50.

Black plate (62,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-62 Driving and Operating
Automatic Braking
If ACP detects it is about to crash
with the vehicle you are following
that is moving or has come to a
stop, and the brakes have not been
applied, it may automatically brake
hard. This can help to reduce crash
damage and it may even help to
avoid some very low speed crashes.
Automatic Braking may slow the
vehicle to a complete stop to try to
avoid a potential crash. The vehicle
will only hold at a stop briefly. A firm
press of the accelerator pedal will
also release Automatic Braking.
{Warning
Automatic Braking may
automatically brake the vehicle
suddenly in situations where it is
unexpected and undesired.
It could respond to a turning
vehicle ahead, guardrails, signs,
and other non-moving objects. To(Continued)
Warning (Continued)
override Automatic Braking, firmly
press the accelerator pedal, if it is
safe to do so.
Automatic Braking can be disabled
or reduced through vehicle
personalization. See the “Auto
Collision Preparation” portion of
“Collision/Detection Systems” under
Vehicle Personalization on
page 5-50.
{Warning
Using the Automatic Collision
Preparation System while towing
a trailer could cause you to lose
control of the vehicle and crash.
Turn the system off when towing
a trailer.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with vehicles in the side blind
zone (or spot) areas. When the
vehicle is moving forward, the left or
right side mirror display will light up
if a vehicle is detected in that blind
zone. If the turn signal is activated
and a vehicle is also detected on
the same side, the display will flash
as an extra warning not to change
lanes. Since this system is part of
the Lane Change Alert system, read
the entire Lane Change Alert
section before using this feature.
Lane Change Alert (LCA)
If equipped, the Lane Change Alert
(LCA) system is a lane-changing aid
that assists drivers with avoiding
lane change crashes that occur with
vehicles in the side blind zone (or
spot) areas or with vehicles rapidly
approaching these areas from

Black plate (78,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
9-78 Driving and Operating
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Instructions about safety chains
may be provided by the hitch
manufacturer or by the trailer
manufacturer. If the trailer being
towed weighs up to 2 271 kg
(5,000 lb) with a factory-installed
step bumper, safety chains may be
attached to the attaching points on
the bumper, otherwise, safety
chains should be attached to holes
on the trailer hitch platform. Always
leave just enough slack so the
combination can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 900 kg (2,000 lb) needs to have
its own brake system that is
adequate for the weight of the
trailer. Be sure to read and followthe instructions for the trailer brakes
so they are installed, adjusted, and
maintained properly.
Since the vehicle is equipped with
StabiliTrak, the trailer brakes cannot
tap into the vehicle's hydraulic
system.
Trailer Wiring Harness
The seven-pin trailer connector is
mounted in the bumper. This
connector can be plugged into a
seven-pin universal heavy-duty
trailer connector available through
your dealer.
The seven-wire harness contains
the following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Green/Violet: Right Stop/Turn
Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red/Green: Battery Feed
.Dark Blue: Trailer BrakeIf charging a remote (non-vehicle)
battery, press the Tow/Haul mode
button at the end of the shift lever.
This will boost the vehicle system
voltage and properly charge the
battery. If the trailer is too light for
Tow/Haul mode, turn on the
headlamps as a second way to
boost the vehicle system and
charge the battery.
Electric Brake Control Wiring
Provisions
These wiring provisions are
included with the vehicle as part of
the trailer wiring package. These
provisions are for an electric brake
controller.
The harness should be installed by
your dealer or a qualified service
center.