
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9955936) - 2017 - crc - 7/5/16
280 Driving and Operating
3. Readjust Trailer Gain any timevehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing.
Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
. The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle. If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off. 3. Wait 10 seconds, then turn the
ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side.
If the CHECK TRAILER
WIRING message only
reappears when connecting the
trailer wiring harness to the
vehicle, the electrical fault is on
the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, there is a problem with the
ITBC system. Have the vehicle
serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 281
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.
A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
being towed. If the vehicle is towing
a trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If the vehicle
is equipped with the Integrated
Trailer Brake Control (ITBC) system,and the trailer has the electric
actuated brake system, StabiliTrak
may also apply the trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on the
instrument cluster. Vehicle speed
must be reduced. If trailer sway
continues, StabiliTrak can reduce
engine torque to help slow the
vehicle. See
Traction Control/
Electronic Stability Control 0239.
{Warning
Even if the vehicle is equipped
with TSC, trailer sway could result
in loss of control and the vehicle
could crash. If excessive trailer
sway is detected, slow down to a
safe speed. Check the trailer and
vehicle to help correct possible
causes. These could include an
improperly or overloaded trailer,
unrestrained cargo, improper
trailer hitch configuration,
excessive vehicle-trailer speed,
or improperly inflated or incorrect
(Continued)
Warning (Continued)
vehicle or trailer tires. See Towing
Equipment 0274 for trailer ratings
and hitch setup
recommendations.
Adding non-dealer accessories can
affect the vehicle performance. See
Accessories and
Modifications 0285.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 283
Vehicle Care
General Information
General Information . . . . . . . . . . 284
California Proposition65 Warning . . . . . . . . . . . . . . . . . 284
California Perchlorate Materials Requirements . . . . . 284
Accessories and Modifications . . . . . . . . . . . . . . . . 285
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 285
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 286
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 287
Engine Oil . . . . . . . . . . . . . . . . . . . . 290
Engine Oil Life System . . . . . . . 292
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 293
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 296
Engine Air Cleaner/Filter . . . . . . 297
Cooling System . . . . . . . . . . . . . . 298
Engine Coolant . . . . . . . . . . . . . . . 299
Engine Overheating . . . . . . . . . . 301
Engine Fan . . . . . . . . . . . . . . . . . . . 303
Washer Fluid . . . . . . . . . . . . . . . . . 303
Brakes . . . . . . . . . . . . . . . . . . . . . . . 304 Brake Fluid . . . . . . . . . . . . . . . . . . . 305
Battery - North America . . . . . . 306
Four-Wheel Drive . . . . . . . . . . . . . 306
Front Axle . . . . . . . . . . . . . . . . . . . . 307
Rear Axle . . . . . . . . . . . . . . . . . . . . 308
Noise Control System . . . . . . . . 308
Starter Switch Check . . . . . . . . . 309
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 310
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 310
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 310
Wiper Blade Replacement . . . . 311
Glass Replacement . . . . . . . . . . 312
Windshield Replacement . . . . . 312
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 312
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 313
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 313
LED Lighting . . . . . . . . . . . . . . . . . 313
Fog Lamps . . . . . . . . . . . . . . . . . . . 313
Back-Up Lamps . . . . . . . . . . . . . . 313
License Plate Lamp . . . . . . . . . . 314
Replacement Bulbs . . . . . . . . . . . 315
Electrical System
Electrical System Overload . . . 315
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 316
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 316
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 320
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 323
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 325
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 326
All-Season Tires . . . . . . . . . . . . . . 327
Winter Tires . . . . . . . . . . . . . . . . . . 327
Low-Profile Tires . . . . . . . . . . . . . 328
All-Terrain Tires . . . . . . . . . . . . . . . 328
Tire Sidewall Labeling . . . . . . . . 328
Tire Designations . . . . . . . . . . . . . 330
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 330
Tire Pressure . . . . . . . . . . . . . . . . . 333
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 334
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 335
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 336
Tire Inspection . . . . . . . . . . . . . . . . 339
Tire Rotation . . . . . . . . . . . . . . . . . 339

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 303
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.
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. SeeEngine
Compartment Overview 0287 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.
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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310 Vehicle Care
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. 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
If equipped with a key access
ignition, 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.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 319
ItemUsage
48 Upfitter 4 relay
49 Reverse lamps
50 –
51 Parking lamp relay
52 –
53 –
54 –
55 –
56 –
57 –
58 –
59 Euro trailer
60 A/C control
61 –
62 –
63 Upfitter 1
64 –
65 –
66 –
67 Trailer battery Item
Usage
68 –
69 RC upfitter 3 and 4
70 VBAT upfitter 3 and 4
71 –
72 Upfitter 1 relay
73 –
74 Engine control module ignition
75 Miscellaneous ignition spare
76 Transmission ignition
77 RC upfitter 1 and 2
78 VBAT upfitter 1 and 2
79 –
80 –
81 –
82 –
83 Euro trailer/RC
84 Run/Crank relay Item
Usage
85 –
86 –
87 Engine
88 Injector A –odd
89 Injector B –even
90 O2 sensor B
91 Throttle control
92 Engine control module relay
93 Horn
94 Fog lamps
95 High-beam headlamps
96 –
97 –
98 –
99 –
100 O2 sensor A
101 Engine control module

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 321
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Item Usage
1 –
2 – Item Usage
3 –
4 Accessory power outlet 1
5 Retained accessory power
6 APO/BATT
7 Universal garage door opener/Interior
rearview mirror
8 SEO/Retained accessory power
9 –
10 Body control module 3
11 Body control module 5
12 Steering wheel control backlighting
13 –
14 –
15 –
16 Discrete logic ignition sensor
17 Video processing module

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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322 Vehicle Care
ItemUsage
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
30 –
31 –
32 – Item
Usage
33 SEO/Automatic level control
34 Park enable/Electric adjustable pedal (if
equipped)
35 –
36 Miscellaneous/RC
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
44 Driver power seat
45 –
46 Right heated, cooled, or ventilated seat (if
equipped) Item
Usage
47 Left heated, cooled, or ventilated seat (if
equipped)
48 –
49 –
50 Accessory power outlet 2
51 –
52 Retained accessory power relay
53 Run/Crank relay
54 –
55 –
56 –