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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
264 Driving and Operating
.The trailer must be equipped
with brakes adequate for the
intended use. A loaded trailer
weighing more than 900 kg
(2,000 lb) must be equipped with
its own brake system, with
brakes working on all axles.
Trailer braking equipment
conforming to Canadian
Standards Association (CSA)
requirement CAN3-D313, or its
equivalent, is recommended.
. Do not tow a trailer during the
first 800 km (500 mi) to prevent
damage to the engine, axle,
or other parts.
. Then during the first 800 km
(500 mi) of trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
. 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.
. Do not use Adaptive Cruise
Control when towing. .
Turn off Parking Assist and Rear
Cross Traffic Alert (RTCA) when
towing.
. The Forward Automatic Braking
System should be set to Off
when towing. See Forward
Automatic Braking (FAB) 022.
. Turn off Lane Keep Assist (LKA)
when towing. See Lane Keep
Assist (LKA) 0257.
{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
When towing a trailer:
. Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
. Fully open the air outlets on
or under the instrument
panel.
(Continued)
Warning (Continued)
.Also adjust the climate
control system to a setting
that brings in only outside
air. See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0219.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
The structure, tires, and brakes of
the trailer must be rated to carry the
load. Inadequate trailer equipment
can cause the combination to
operate in an unexpected or unsafe
manner.
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
Vehicle Care 299
If Steam is Coming from the
Engine Compartment
{Warning
Steam 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
0 266.
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.
Page 319 of 431
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
318 Vehicle Care
FusesUsage
105 –
106 –
107 Aeroshutter
108 –
109 Police upfitter
110 –
111 –
113 –
114 Front windshield washer
115 Rear window washer
116 Left cooling fan
117 Fuel pump prime
118 –
119 –
120 –
121 Right HID headlamp
122 Left HID headlamp
123 Right cooling fan Relays
Usage
9 Fuel pump
29 Upfitter 2
37 Upfitter 3
48 Upfitter 4
51 Parking lamp
64 Secondary fuel pump
72 Upfitter 1
84 Run/Crank
92 Engine control module
112 Starter
120 Fuel pump primeInstrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.
Pull off the cover to access the fuse
block.
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
320 Vehicle Care
FusesUsage
17 Video processing module
18 Mirror window module
19 Body control module 1
20 Front bolster (if equipped)
21 –
22 –
23 –
24 HVAC/Ignition
25 Instrument cluster/ Ignition sensing
diagnostic module/
Ignition
26 Tilt column/SEO/Tilt column lock 1/SEO
27 Data link connector/ Driver seat module
28 Passive entry/Passive start/HVAC battery
29 Content theft deterrent Fuses
Usage
30 –
31 –
32 –
33 SEO/Automatic level control/Left heated
second row seat
34 Park enable/Electric adjustable pedal (if
equipped)
35 –
36 Miscellaneous/Run crank
37 Heated steering wheel
38 Steering column lock 2 (if equipped)
39 Instrument cluster battery
40 –
41 –
42 Euro trailer (if equipped)
43 Left doors Fuses
Usage
44 Driver power seat
45 –
46 Right heated, cooled, or ventilated seat (if
equipped)
47 Left heated, cooled, or ventilated seat (if
equipped)
48 –
49 –
50 Accessory power outlet 2
51 –
54 –
55 –
56 –
Relays Usage
52 Retained accessory power
53 Run/Crank relay
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
322 Vehicle Care
FusesUsage
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 DC to AC 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 –
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
Vehicle Care 323
RelaysUsage
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
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
19 Rear fog lamp (if equipped)
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
324 Vehicle Care
RelaysUsage
1 Rear window defogger
16 Liftgate
17 Liftglass
18 Rear fog lamp
20 Heated mirrorWheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much
flexing. There could be a
blowout and a serious
crash. See Vehicle Load
Limits 0204.
(Continued)
Warning (Continued)
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are
more likely to be cut,
punctured, or broken by
a sudden impact —such
as when hitting a pothole.
Keep tires at the
recommended pressure.
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
(Continued)
Page 329 of 431

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - CRC - 11/3/17
328 Vehicle Care
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.