2014 GMC YUKON warning

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
Vehicle Care 10-17
Warning (Continued)
cap, is hot. Wait for the cooling
system and surge tank pressure
cap to cool.
If no coolant is visible in the surge
tank, add coolant as follows:
1. Remove the coolant surge tank pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means there
is still some pressure left. 2. Keep turning the pressure cap
slowly and remove it.3. Fill the coolant surge tank withthe proper mixture to the FULL
COLD mark.
4. With the coolant surge tank
pressure cap off, start the
engine and let it run until the
upper radiator hose can be felt
getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge tank
until the level reaches the FULL
COLD mark.
5. Replace the pressure cap tightly.

Black plate (18,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
10-18 Vehicle Care
6. Verify coolant level after engineis shut off and the coolant is
cold. If necessary, repeat coolant
fill procedure Steps 1–6.
Notice: If the pressure cap is not
tightly installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge on your vehicle's instrument
panel. See Engine Coolant
Temperature Gauge on page 5-14.
In addition, ENGINE OVERHEATED
STOP ENGINE, ENGINE
OVERHEATED IDLE ENGINE, and
an ENGINE POWER IS REDUCED
message comes on in the Driver
Information Center (DIC) on the
instrument panel. See Engine
Cooling System Messages on
page 5-36 andEngine Power
Messages on page 5-37. If the decision is made not to lift the
hood when this warning appears,
but instead get service help right
away. See
Roadside Assistance
Program on page 13-5.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, both fans
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
Notice: Running the engine
without coolant may cause
damage or a fire. Vehicle damage
would not be covered by the
warranty. See Overheated Engine
Protection Operating Mode on
page 10-19 for information on
driving to a safe place in an
emergency.
If Steam Is Coming from the
Engine Compartment
{Warning
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Turn it off
and get everyone away from the
vehicle until it cools down. Wait
until there is no sign of steam or
coolant before you open
the hood.
If you keep driving when the
vehicles engine is overheated,
the liquids in it can catch fire. You
or others could be badly burned.
Stop the engine if it overheats,
and get out of the vehicle until the
engine is cool.
(Continued)

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
Vehicle Care 10-19
Warning (Continued)
SeeOverheated Engine
Protection Operating Mode on
page 10-19 for information on
driving to a safe place in an
emergency.
If No Steam Is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem.
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. See Trailer
Towing on page 9-63.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped.
If it is safe to do so, pull off the
road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally. If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle the
engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see
“Overheated
Engine Protection Operating Mode”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message is displayed,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
Vehicle Care 10-21
Notice:Use of the incorrect fluid
may damage the vehicle and the
damages may not be covered by
the vehicle's warranty. Always
use the correct fluid listed in
Recommended Fluids and
Lubricants on page 11-12.
Washer Fluid
What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient
protection against freezing in an
area where the temperature may fall
below freezing.
Adding Washer Fluid
The vehicle has a low washer fluid
message on the DIC that comes on
when the washer fluid is low. The
message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID message displays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See
Engine
Compartment Overview on
page 10-5 for reservoir location.
Notice
.When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
.Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
.Fill the washer fluid tank only
three-quarters full when it is
very cold. This allows for
fluid expansion if freezing
occurs, which could damage
the tank if it is
completely full.
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
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.

Black plate (22,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
10-22 Vehicle Care
{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.
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid. See
Engine Compartment Overview on
page 10-5 for the location of the
reservoir.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
Vehicle Care 10-23
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 5-21.
Refer to the Maintenance Schedule
to determine when to check the
brake fluid. See Maintenance
Schedule on page 11-2.
Checking Brake Fluid
Check brake fluid by looking at the
brake fluid reservoir. See Engine
Compartment Overview on
page 10-5.
The fluid level should be above
MIN. If it is not, have the brake
hydraulic system checked to see if
there is a leak.
After work is done on the brake
hydraulic system, make sure the
level is above the MIN but not over
the MAX mark.
What to Add
Use only new DOT 3 brake fluid
from a sealed container. See
Recommended Fluids and
Lubricants on page 11-12.

Black plate (24,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
10-24 Vehicle Care
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it. This
helps keep dirt from entering the
reservoir.
{Warning
With the wrong kind of fluid in the
brake hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake fluid.
Notice
.Using the wrong fluid can
badly damage brake
hydraulic system parts. For
example, just a few drops of
mineral-based oil, such as
engine oil, in the brake
hydraulic system can
damage brake hydraulic
system parts so badly that
they will have to be replaced.
Do not let someone put in
the wrong kind of fluid.
.If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Be careful not to
spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery
Refer to the replacement number on
the original battery label when a
new battery is needed. See Engine
Compartment Overview on
page 10-5 for battery location.
{Warning
Battery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. See Jump Starting on
page 10-76 for tips on working
around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative (−) cable from the
battery or use a battery trickle
charger.

Black plate (27,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada-
6081505) - 2014 - crc - 4/23/13
Vehicle Care 10-27
The proper level is from 1.0 mm to
19.0 mm (0.04 in to 0.75 in) below
the bottom of the fill plug hole,
located on the rear axle. Add only
enough fluid to reach the proper
level.
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts. 3. Try to start the engine in each
gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface. 2. Firmly apply the parking brake.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.