warning light GMC YUKON 2012 Service Manual

Black plate (51,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-51
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. If the vehicle has StabiliTrak and the
system begins to limit wheel spin,
cruise control will automatically
disengage. See
StabiliTrak
®System
on page 9‑46. 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.

Black plate (53,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-53
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.
Object Detection
Systems
Ultrasonic Parking Assist
If available, the Ultrasonic Rear
Parking Assist (URPA) system uses
sensors on the rear bumper to
assist with parking and avoiding
objects while in R (Reverse).
{WARNING
The URPA system does not
detect pedestrians, bicyclists,
animals, or any other objects
located below the bumper or that
are too close or too far from the
vehicle. To prevent injury, death,
or vehicle damage, even with
URPA, always check behind the
vehicle and check all mirrors
before backing.
How the System Works
URPA comes on automatically
when the shift lever is moved into
R (Reverse). A single tone sounds
to indicate the system is working.
URPA operates only at speeds less
than 8 km/h (5 mph).
An obstacle is indicated by
audible beeps. The time between
the beeps gets shorter as the
vehicle approaches the obstacle.
A continuous tone is heard when
the distance is less than
30 cm (12 in).
To be detected, objects must be at
least 25 cm (10 in) off the ground
and below liftgate level. Objects
must also be within 2.5 m (8 ft) from
the rear bumper. This distance may
be less during warmer or humid
weather.

Black plate (54,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-54 Driving and Operating
Turning the System On and Off
Press this button, located next to
the radio, to disable URPA.
The indicator light comes on and
PARK ASSIST OFF displays on the
Driver Information Center (DIC).
SeeObject Detection System
Messages on page 5‑42.
When the System Does Not
Seem to Work Properly
The following messages may be
displayed on the DIC:
SERVICE PARK ASSIST: this
message occurs, take the vehicle to
your dealer for repair. PARK ASSIST OFF:
This message
occurs if the driver disables the
system or if the vehicle is driven
above 8 km/h (5 mph) in
R (Reverse).
PARK ASST BLOCKED SEE
OWNERS MANUAL: This
message can occur under the
following conditions:
.The ultrasonic sensors are not
clean. Keep the rear bumper
free of mud, dirt, snow, ice,
slush, and frost. The message
may not clear until frost or ice
has melted all around and inside
the sensor.
.A trailer is attached to the
vehicle, or a bicycle or an object
hanging out of the liftgate during
the current or last drive cycle.
URPA will return to normal
operation after it is determined
the object is removed. This
could take a few drive cycles.
.A tow bar is attached to the
vehicle. Other conditions may affect system
performance, such as vibrations
from a jackhammer or the
compression of air brakes on a
very large truck.
Side Blind Zone
Alert (SBZA)
If available, the Side Blind Zone
Alert system is a lane changing aid
that assists drivers with avoiding
crashes that occur with vehicles in
the side blind zones.
{WARNING
SBZA does not detect vehicles
rapidly approaching outside of the
side blind zones, pedestrians,
bicyclists, or animals. Failure to
use proper care when changing
lanes may result in injury, death,
or vehicle damage. Always check
for other vehicles and use the
turn signals when changing lanes.

Black plate (55,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-55
SBZA Detection Zones
The SBZA sensor covers a zone of
approximately one lane over from
both sides of the vehicle, 3.5 m
(11 ft). This zone starts at each side
mirror and goes back approximately
5.0 m (16 ft). The height of the
zone is approximately between
0.5 m (1.5 ft) and 2.0 m (6 ft) off the
ground.
Use caution while changing lanes
when towing a trailer, as the SBZA
detection zones do not change
when a trailer is towed.How the System Works
The SBZA symbol lights up in the
side mirrors when the system
detects a vehicle in the side blind
zone, indicating it may be unsafe to
change lanes. Before making a lane
change, check the SBZA display,
check all mirrors, glance over your
shoulder, and use the turn signals.
Left Side Mirror
DisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror SBZA displays will
briefly come on to indicate the
system is operating. 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
to give you extra warning not to
change lanes.
At speeds greater then 32 km/h
(20 mph), SBZA displays may come
on when approaching or passing
other vehicles. SBZA displays may
come on when a passed vehicle
remains in or drops back into the
detection zone. SBZA can be
disabled through the Driver
Information Center (DIC). See
Driver
Information Center (DIC) on
page 5‑29. If SBZA is disabled by
the driver, the SBZA mirror displays
will not light up.
When the System Does Not Seem
To Work Properly
Missed alerts can occur under
normal circumstances and will
increase in wet conditions. The
system does not need to be
serviced. SBZA is designed to
ignore stationary objects; however,
the system may occasionally light
up due to guard rails, signs, trees,

Black plate (57,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-57
Such modifications could void the
user's authority to operate the
equipment.
Rear Vision
Camera (RVC)
If available, the Rear Vision Camera
(RVC) system displays part of the
scene behind the vehicle.
{WARNING
The RVC system does not display
pedestrians, bicyclists, animals,
or any other object located
outside the camera's field of view,
below the bumper, or under the
vehicle.
Do not back the vehicle using
only the RVC screen or by using
the screen during longer, higher
speed backing maneuvers,
or where there could be(Continued)
WARNING (Continued)
cross-traffic. Perceived distances
may be different from actual
distances.
Failure to use proper care before
backing may result in injury,
death, or vehicle damage. Always
check before backing by checking
behind and around the vehicle.
Vehicles without Navigation
System
The RVC system displays a view of
the area behind the vehicle. When
the vehicle is on and shifted into
R (Reverse) the video image
appears on the inside rearview
mirror. The video image disappears
after the vehicle is shifted out of
R (Reverse). Turning the RVC System On or Off
To turn off the RVC system, press
and hold
z, located on the inside
rearview mirror, until the left
indicator light turns off. The RVC
display is now disabled.
To turn the RVC system on, press
and hold
zuntil the left indicator
light comes on. The RVC system
display will appear in the mirror.
Vehicles with Navigation
System
The RVC system is designed to
help the driver when backing up by
displaying a view of the area behind
the vehicle. When the vehicle is
shifted into R (Reverse), the video
image appears on the navigation
screen. After a delay, the navigation
screen displays the last screen after
the vehicle is shifted out of
R (Reverse).

Black plate (66,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-66 Driving and Operating
While refueling, hang the tethered
fuel cap from the hook on the
fuel door.
{WARNING
Fuel can spray out on you if you
open the fuel cap too quickly.
If you spill fuel and then
something ignites it, you could be
badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and wait
for any hiss noise to stop. Then
unscrew the cap all the way.
Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10‑98. When replacing the fuel cap, insert
the tether in its hole before
tightening the cap. Turn the fuel cap
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. See
Malfunction
Indicator Lamp on page 5‑21.
If the vehicle has a Driver
Information Center (DIC), the
TIGHTEN GAS CAP message
displays if the fuel cap is not
properly installed.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer. The
wrong type of fuel cap might not
fit properly, might cause the
malfunction indicator lamp to
light, and could damage the fuel
tank and emissions system. See
Malfunction Indicator Lamp on
page 5‑21.

Black plate (70,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-70 Driving and Operating
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal. Do this
so the trailer will not strike soft
shoulders, curbs, road signs, trees
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn
out, the arrows on the instrument
panel will still flash for turns. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the transmission is not shifted down, the
brakes might get hot and no longer
work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
The tow/haul mode may be used if
the transmission shifts too often.
See
Tow/Haul Mode Light on
page 5‑25.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑21.
Parking on Hills
{WARNING
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if facing
downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer wheels.

Black plate (86,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-86 Driving and Operating
Trailer Sway
Control (TSC)
Non-hybrid vehicles with StabiliTrak
have a Trailer Sway Control (TSC)
feature. If the vehicle is towing a
trailer and the system detects that
the trailer is swaying, the vehicle
brakes are applied without the driver
pressing the brake pedal. If the
vehicle is equipped with the
Integrated Trailer Brake Control
(ITBC) system, StabiliTrak may also
apply the trailer brakes. The TCS/
StabiliTrak warning light will flash on
the instrument panel cluster to notify
the driver to reduce speed. If the
trailer continues to sway, StabiliTrak
will reduce engine torque to help
slow the vehicle. SeeStabiliTrak
®
System on page 9‑46 for more
information.
Adding non‐dealer accessories can
affect the vehicle performance. See
Accessories and Modifications on
page 10‑3 for more information.
Conversions and
Add-Ons
Add-On Electrical
Equipment
Notice:Do not add anything
electrical to the vehicle unless
you check with your dealer first.
Some electrical equipment can
damage the vehicle and the
damage would not be covered by
the vehicle's warranty. Some
add-on electrical equipment can
keep other components from
working as they should.
Add-on equipment can drain the
vehicle's 12‐volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle on page 3‑42 andAdding
Equipment to the Airbag-Equipped
Vehicle on page 3‑42.
Adding a Snow Plow or
Similar Equipment
Before installing a snow plow on the
vehicle, here are some things you
need to know:
Notice: If the vehicle does not
have the snow plow prep
package, adding a plow can
damage the vehicle, and the
repairs would not be covered by
warranty. Unless the vehicle was
built to carry a snow plow, do not
add one to the vehicle. If the
vehicle has the snow plow prep
package, called RPO VYU, then
the payload the vehicle can carry
will be reduced when a snow
plow is installed. The vehicle can
be damaged if either the front or
rear axle ratings or the Gross
Vehicle Weight (GVW) are
exceeded.

Black plate (26,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-26 Vehicle Care
Brakes
This vehicle has disc brakes. Disc
brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications in
Capacities and
Specifications on page 12‑2.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes —for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.

Black plate (27,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-27
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid. See
Engine Compartment Overview on
page 10‑6for the location of the
reservoir.
There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also cause
a low fluid level. Have the brake
hydraulic system fixed, since a
leak means that sooner or later
the brakes will not work well. Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
{WARNING
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system. See
“Checking Brake
Fluid” in this section.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light on page 5‑23. Refer to the Maintenance Schedule
to determine when to check the
brake fluid. See
Maintenance
Schedule on page 11‑3.
Checking Brake Fluid
Check brake fluid by looking at the
brake fluid reservoir. See Engine
Compartment Overview on
page 10‑6.
The fluid level should be above
MIN. If it is not, have the brake
hydraulic system checked to see if
there is a leak.