2018 GMC YUKON XL air condition

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 295If Steam is Coming from the
Engine Compartment
{ WarningSteam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
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 there is an engine overheat
warning, but no steam is 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
0 262 .
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so:
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. When it is safe to do so, pull off
the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the engine coolant temperature
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 and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam and
the vehicle is equipped with an
engine driven cooling fan, push
down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
five minutes while the vehicle is
parked. If the warning is still there,
turn off the engine and get everyone
out of the vehicle until it cools down.
If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
296 Vehicle Care
Engine Fan If the vehicle has electric cooling
fans, the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned. off. This is normal and no
service is required.
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 0 280 for
reservoir location. Caution .
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
.
Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
.
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.
.
When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
.
Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 297Caution (Continued) freezing occurs, which could
damage the tank if it is
completely full.
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 can
be heard all the time when 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. CautionContinuing 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. See Capacities and
Specifications 0 384 .
Brake pads should be replaced as
complete 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 may be required. Replacing Brake System Parts Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or if parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with GM approved DOT 3
brake fluid as indicated on the
reservoir cap. See Engine
Compartment Overview 0 280 for
the location of the reservoir.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 313Fuses Usage
55 –
56 –
57 –
58 –
59 Euro trailer
60 Air conditioning
control
61 –
62 –
63 Upfitter 1
64 –
65 –
66 –
67 Trailer battery
68 Secondary
fuel pump
69 RC upfitter 3 and 4
70 VBAT
upfitter 3 and 4
71 –
73 – Fuses Usage
74 Engine control
module/Ignition
75 Miscellaneous/
Ignition/ –
76 Transmission/
Ignition
77 RC upfitter 1 and 2
78 VBAT
upfitter 1 and 2
79 –
80 –
81 –
82 –
83 Euro trailer/RC
85 –
86 –
87 Engine
88 Injector A – odd
89 Injector B – even
90 O2 sensor B
91 Throttle control Fuses Usage
93 Horn
94 Fog lamps
95 High-beam
headlamps
96 –
97 –
98 –
99 –
100 O2 sensor A
101 Engine control
module
102 Engine control
module/
Transmission
control module
103 Auxiliary interior
heater
104 Starter
105 –
106 –
107 Aeroshutter
108 –

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
318 Vehicle Care Fuses Usage
3 –
4 Accessory power
outlet 4
5 –
6 –
7 –
8 Glove box
9 –
10 –
11 –
12 Steering wheel
controls
13 Body control module 8
14 –
15 –
16 –
17 –
18 –
19 Body control module 4
20 Rear seat
entertainment Fuses Usage
21 Sunroof
22 –
23 –
24 –
25 –
26 Infotainment/Airbag
27 – /RF window switch/
Rain sensor
28 Obstacle
detection/USB
29 Radio
30 –
31 –
32 –
33 –
34 –
35 –
36 Special equipment
option B2
37 Special equipment
option Fuses Usage
38 Body control module 2
39 Air conditioning
inverter
40 –
41 –
42 –
43 –
44 Right door window
motor
45 Front blower
46 Body control module 6
47 Body control module 7
48 Amplifier
49 Right front seat
50 Accessory power
outlet 3
51 –
53 –
54 –
55 –
56 –

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 319Relays Usage
52 Retained accessory
power
Rear Compartment Fuse
Block
The rear compartment fuse block is
behind the access panel on the left
side of the compartment.
Pull the panel out by grabbing the
finger access slot at the rear edge. The vehicle may not be equipped
with all of the fuses, relays, and
features shown. Fuses Usage
1 Rear window
defogger relay
2 –
3 Right heated second
row seat
4 Heated mirrors
5 Liftgate
6 Glass breakage
7 Liftglass
8 Liftgate module logic
9 Rear wiper
10 Rear heating,
ventilation, and air
conditioning blower
11 Second row seat
12 Liftgate module
13 Third row seat
14 Rear accessory power
outlet
15 Rear window
defogger
16 Liftgate

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 321Warning (Continued).
Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc..
Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires..
Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.
See Tire Pressure for
High-Speed Operation 0 328 for
inflation pressure adjustment for
high-speed driving. All-Season Tires This vehicle may come with
all-season tires. These tires are
designed to provide good overall
performance on most road surfaces
and weather conditions. Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. Original
equipment all-season tires can be
identified by the last two characters
of this TPC code, which will
be “ MS. ”
Consider installing winter tires on
the vehicle if frequent driving on
snow or ice-covered roads is
expected. All-season tires provide
adequate performance for most
winter driving conditions, but they
may not offer the same level of
traction or performance as winter
tires on snow or ice-covered roads.
See Winter Tires 0 321 .
Winter Tires This vehicle was not originally
equipped with winter tires. Winter
tires are designed for increased traction on snow and ice-covered
roads. Consider installing winter
tires on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your dealer
for details regarding winter tire
availability and proper tire selection.
Also, see Buying New Tires 0 335 .
With winter tires, there may be
decreased dry road traction,
increased road noise, and shorter
tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
.
Use tires of the same brand and
tread type on all four wheel
positions.
.
Use only radial ply tires of the
same size, load range, and
speed rating as the original
equipment tires.
Winter tires with the same speed
rating as the original equipment tires
may not be available for H, V, W, Y,
and ZR speed rated tires. If winter

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
324 Vehicle Care
Tire Designations Tire Size
The example shows a typical
passenger vehicle tire size.
Passenger (P-Metric) Tire
(1) Passenger (P-Metric) Tire :
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.
(2) Tire Width :
The three-digit
number indicates the tire section
width in millimeters from
sidewall to sidewall. (3) Aspect Ratio :
A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 75, as shown in
item C of the tire illustration, it
would mean that the tire's
sidewall is 75 percent as high as
it is wide.
(4) Construction Code :
A letter
code is used to indicate the type
of ply construction in the tire.
The letter R means radial ply
construction; the letter D means
diagonal or bias ply
construction; and the letter B
means belted-bias ply
construction.
(5) Rim Diameter :
Diameter of
the wheel in inches.
(6) Service Description :
These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions Air Pressure :
The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Accessory Weight :
The
combined weight of optional
accessories. Some examples of
optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio :
The relationship
of a tire's height to its width.
Belt :
A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials.