2013 GMC YUKON brake light

Black plate (42,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
9-42 Driving and Operating
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 might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver 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.
SeeBrake System Warning Light on
page 5‑21.
Notice: 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 9‑63.
Brake Assist
This vehicle has a brake assist
feature 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

Black plate (45,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Driving and Operating 9-45
the appropriate DIC message
displays. This will also disable the
TSC feature.
Traction control and StabiliTrak can
be turned on by pressing and
releasing the TCS/StabiliTrak button
if they are not automatically shut off
for any other reason. This will also
enable the TSC feature.
When the TCS or StabiliTrak system
is turned off, the StabiliTrak light
and the appropriate message will be
displayed on the DIC to warn the
driver. The vehicle will still have
brake-traction control when traction
control is off, but will not be able to
use the engine speed management
system. See“Traction Control
Operation” next for more
information.
When the TCS has been turned off,
system noises may still be heard as
a result of the brake-traction control
coming on.
It is recommended to leave the
system on for normal driving
conditions, but it may be necessary to turn the system off if the vehicle
is stuck in sand, mud, ice or snow,
and you want to
“rock”the vehicle to
attempt to free it. It may also be
necessary to turn off the system
when driving in extreme off-road
conditions where high wheel spin is
required. See If the Vehicle Is Stuck
on page 9‑15.
When the transfer case is in 4LO,
the stability system is automatically
disabled, the StabiliTrak light comes
on, and the appropriate message
will appear on the DIC. Both traction
control and StabiliTrak are
automatically disabled in this
condition.
Traction Control Operation
The TCS is part of the StabiliTrak
system. Traction control limits wheel
spin by reducing engine power to
the wheels (engine speed
management) and by applying
brakes to each individual wheel
(brake-traction control) as
necessary. The TCS is enabled automatically
when the vehicle is started. It will
activate and the StabiliTrak light will
flash if it senses that any of the
wheels are spinning or beginning to
lose traction while driving. If traction
control is turned off, only the
brake-traction control portion of
traction control will work. The
engine speed management will be
disabled. In this mode, engine
power is not reduced automatically
and the driven wheels can spin
more freely. This can cause the
brake-traction control to activate
constantly.
Notice:
If the wheel(s) of one axle
is allowed to spin excessively
while the StabiliTrak
®, ABS, brake
warning lights, and any relevant
DIC messages are displayed, the
transfer case could be damaged.
The repairs would not be covered
by the vehicle warranty. Reduce
engine power and do not spin the
wheel(s) excessively while these
lights and messages are
displayed.

Black plate (47,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Driving and Operating 9-47
Automatic Level Control
The automatic level control rear
suspension is available on light‐duty
vehicles and comes as a part of the
Continuous Damping Control (CDC)
suspension, if equipped.
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
ten 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. So, do not use
the 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).
When the brakes are applied, cruise
control is turned off.

Black plate (48,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
9-48 Driving and Operating
If the vehicle has StabiliTrak and the
system begins to limit wheel spin,
cruise control will automatically
disengage. SeeStabiliTrak
®System
on page 9‑43. When road conditions
allow the cruise control to be safely
used again, it can be turned
back on.
I(On/Off): Press to turn the
system on or off. The indicator light
is on when cruise control is on and
turns off when cruise control is off. +RES (Resume/Accelerate):
Press briefly to make the vehicle
resume to a previously set speed,
or press and hold to accelerate.
SET−
(Set/Coast): Press to set the
speed and activate cruise control or
make the vehicle decelerate.
[(Cancel): Press to disengage
cruise control without erasing the
set speed from memory.
Setting Cruise Control
If the cruise button is on when not in
use, it could get bumped and go into
cruise when not desired. Keep the
cruise control switch off when cruise
is not being used.
The cruise control light on the
instrument panel cluster comes on
after the cruise control has been set
to the desired speed.
1. Press the
Ibutton.
2. Get up to the desired speed.
3. Press the SET− button located
on the steering wheel and
release it. 4. Take your foot off the
accelerator.
Resuming a Set Speed
If the cruise control is set at a
desired speed and then the brakes
are applied, the cruise control is
disengaged without erasing the set
speed from memory.
Once the vehicle speed reaches
about 40 km/h (25 mph) or more,
press the +RES button on the
steering wheel. The vehicle returns
to the previous set speed and stays
there.
Increasing Speed While Using
Cruise Control
If the cruise control system is
already activated,
.Press and hold the +RES button
on the steering wheel until the
desired speed is reached, then
release it.

Black plate (49,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Driving and Operating 9-49
.To increase vehicle speed in
small amounts, press the +RES
button. Each time this is done,
the vehicle goes about 1.6 km/h
(1 mph) faster.
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated,
.Press and hold the SET– button
on the steering wheel until the
desired lower speed is reached,
then release it.
.To slow down in small amounts,
press the SET– button on the
steering wheel briefly. Each time
this is done, the vehicle goes
about 1.6 km/h (1 mph) slower.
Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previous set cruise speed. 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 5‑42.For other forms of Grade Braking,
see
Automatic Transmission on
page 9‑29 andTow/Haul Mode on
page 9‑33.
Ending Cruise Control
There are three ways to end cruise
control:
.To disengage cruise control,
step lightly on the brake pedal.
.Press the[on the steering
wheel.
.To turn off the cruise control,
press
Ion the steering wheel.
Erasing Speed Memory
The cruise control set speed is
erased from memory by pressing
the
Ibutton or if the ignition is
turned off.

Black plate (72,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
9-72 Driving and Operating
Trailer Brakes
A loaded trailer that weighs more
than 900 kg (2,000 lbs) needs to
have its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the 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 vehicle is equipped with the
following wiring harnesses for
towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
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
.Dark Green: Right Stop/Turn
Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are
installed in the underhood electrical
center, but the wires are not
connected. They should be
connected by your dealer or a
qualified service center. Heavy-Duty Trailer Wiring Harness
Package
The vehicle is equipped with the
seven-wire trailer towing harness.
This harness with a seven-pin
universal trailer connector is
attached to a bracket on the hitch
platform.
The seven-wire harness contains
the following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn
Signal
.Brown: Taillamps

Black plate (73,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
Driving and Operating 9-73
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are
installed in the underhood electrical
center, but the wires are not
connected. They should be
connected by your dealer or a
qualified service center.
If charging a remote (non-vehicle)
battery, press the tow/haul mode
button located 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 instrument panel
contains blunt cut wires near the
data link connector for the trailer
brake controller. The harness
contains the following wires:
.Dark Blue: Brake Signal to
Trailer Connector
.Red/Black: Battery
.Light Blue/White: Brake Switch
.White: Ground
It should be installed by your dealer
or a qualified service center.
If the vehicle is equipped with an
ITBC, the blunt cuts exist, but are
not connected further in the
harness. If an aftermarket trailer
brake controller is installed, the
ITBC must be disconnected. Do not power both ITBC and aftermarket
controllers to control the trailer
brakes at the same time.
Tow/Haul Mode
Pressing this button at the end of
the shift lever turns on and off the
tow/haul mode.
This indicator light on the instrument
panel cluster comes on when the
tow/haul mode is on.

Black plate (74,1)GMC Yukon/Yukon XL Owner Manual - 2013 - CRC 2nd edition - 8/15/12
9-74 Driving and Operating
Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. SeeTow/Haul
Mode on page 9‑33 for more
information.
Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75 percent of the vehicle's Gross
Combined Weight Rating (GCWR).
See “Weight of the Trailer” earlier in
the section. Tow/Haul is most useful
under the following driving
conditions:
.When pulling a heavy trailer or a
large or heavy load through
rolling terrain.
.When pulling a heavy trailer or a
large or heavy load in stop and
go traffic.
.When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired. Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
at all will not cause damage.
However, there is no benefit to the
selection of Tow/Haul when the
vehicle is unloaded. Such a
selection when unloaded may result
in unpleasant engine and
transmission driving characteristics
and reduced fuel economy. Tow/
Haul is recommended only when
pulling a heavy trailer or a large or
heavy load.
Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for electric trailer brakes.
This symbol is located on the Trailer
Brake Control Panel on vehicles
with an Integrated Trailer Brake
Control System. The power output
to the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle’s brake
system. This available power output
to the trailer brakes can be adjusted
to a wide range of trailering
situations.
The ITBC system is integrated with
the vehicle’
s brake, anti-lock brake
and StabiliTrak systems. In trailering
conditions that cause the vehicle’s
anti-lock brake or StabiliTrak
systems to activate, power sent to
the trailer's brakes will be
automatically adjusted to minimize
trailer wheel lock-up. This does not
imply that the trailer has the
StabiliTrak system.
The vehicle may have a Trailer
Sway Control (TSC) feature. See
Trailer Sway Control (TSC) on
page 9‑80.