trailer GMC SIERRA 2018 Repair Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
382 Vehicle Care
Lift the cover to access the fuse
block.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the
covers on any electrical
component.
A fuse puller is available in the left
instrument panel fuse block.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
Fuses Usage
1 Trailer brake Fuses
Usage
2 Trailer battery

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 383
FusesUsage
3 Antilock brake system pump
4 Instrument panel BEC 1
5 Passenger motorized seat belt
6 4WD transfer case electronic control
7 Electric park brake
8 Instrument panel BEC 2
9 Driver motorized seat belt
10 Rear window defogger
11 Starter
12 Cooling fan 1
13 Cooling fan 2
14 Left trailer stop/ Turn signal lamps
15 Trailer parking lamps Fuses
Usage
16 Trailer reverse lamps
17 Right trailer stop/ Turn signal lamps
18 Fuel pump
19 Integrated chassis control module
20 Electronic suspension control
module
21 Fuel pump power module
22 Upfitter 1
23 Upfitter 2
24 Front wiper
25 Antilock brake system valve
26 Upfitter 2
27 Upfitter 3
28 Right parking lamps
29 Left parking lamps Fuses
Usage
30 Upfitter 3
31 Upfitter 4
32 Upfitter 4
33 Reverse lamps
34 Engine control module/Ignition
35 Air conditioning clutch
36 Heated mirrors
37 Upfitter 1
38 Center high-mounted
stoplamp
39 Miscellaneous/ Ignition
40 Transmission/ Ignition
41 Fuel pump 2
42 Cooling fan clutch
43 Engine
44 Fuel injectors A–odd

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
384 Vehicle Care
FusesUsage
45 Fuel injectors B–even
46 O2 Sensor B
47 Throttle control
48 Horn
49 Fog lamps
50 O2 Sensor A
51 Engine control module
52 Interior heater
53 Accessory power module/TPM pump
54 Front washer
55 Air conditioning/ Battery regulated
voltage control
56 Air conditioning module/
Battery pack
57 Transmission control module/
Engine control
module Fuses
Usage
58 Headlamps
74 Electric running boards (if
equipped)
76 Fuel pump prime / MGU motor
77 Cabin pump motor
79 Vacuum pump
Relays Usage
59 Fuel pump
60 Upfitter 2
61 Upfitter 3
62 Upfitter 4
63 Trailer parking lamps
64 Run/Crank
65 Upfitter 1
66 Fuel pump 2
67 Air conditioning control
68 Starter Relays
Usage
69 Rear window defogger
70 Engine control module
71 Vacuum pump/ Cooling fan clutch
72 CKT 95
73 CKT 92
75 Fuel pump prime/ MGU motor
78 Vacuum pump switch

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
392 Vehicle Care
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(5) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(6) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more
information, see Uniform Tire
Quality Grading 0410. (7) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load. For
information on recommended
tire pressure see Tire Pressure
0 397 and Vehicle Load Limits
0 248.
(8) Temporary Use Only
:Only
use a temporary spare tire until
the road tire is repaired and
replaced. This spare tire should
not be driven on over 112 km/h
(70 mph), or 88 km/h (55 mph)
when pulling a trailer, with the
proper inflation pressure. See
Full-Size Spare Tire 0425.
Light Truck (LT-Metric) Tire
(1) Tire Size:The tire size code
is a combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section for more detail.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 425
3. Assemble the wheel blocks (2)and jack (7) together with the
wing nut (1) and retaining
bolt (8).
4. Position the jack (7) in the mounting bracket (6). Position
the holes in the base of the
jack (7) onto the pin in the
mounting bracket (6).
5. Return them to their original location in the vehicle. See
“Removing the Spare Tire and
Tools.”
Full-Size Spare Tire
If this vehicle came with a full-size
spare tire, it was fully inflated when
new, however, it can lose air over
time. Check the inflation pressure
regularly. See Tire Pressure0397
and Vehicle Load Limits 0248. For
instructions on how to remove,
install, or store a spare tire, see Tire
Changing 0415.
If equipped with a temporary use
full-size spare tire, it is indicated on
the tire sidewall. See Tire Sidewall
Labeling 0391. This spare tire should not be driven on over
112 km/h (70 mph), or 88 km/h
(55 mph) when pulling a trailer, at
the proper inflation pressure. Repair
and replace the road tire as soon as
it is convenient, and stow the spare
tire for future use.
Caution
If the vehicle has four-wheel drive
and a different size spare tire is
installed, do not drive in
four-wheel drive until the flat tire
is repaired and/or replaced. The
vehicle could be damaged and
the repairs would not be covered
by the warranty. Never use
four-wheel drive when a different
size spare tire is installed on the
vehicle.
The vehicle may have a different
size spare tire than the road tires
originally installed on the vehicle.
This spare tire was developed for
use on this vehicle, so it is all right
to drive on it. If the vehicle has four-wheel drive and a different size
spare tire is installed, drive only in
two-wheel drive.
After installing the spare tire on the
vehicle, stop as soon as possible
and check that the spare tire is
correctly inflated.
Have the damaged or flat road tire
repaired or replaced and installed
back onto the vehicle as soon as
possible so the spare tire will be
available in case it is needed again.
Do not mix tires and wheels of
different sizes, because they will not
fit. Keep your spare tire and its
wheel together. If the vehicle has a
spare tire that does not match the
original road tires and wheels in size
and type, do not include the spare in
the tire rotation.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 431
recreational vehicle towing are
dinghy and dolly towing. Dinghy
towing is towing the vehicle with all
four wheels on the ground. Dolly
towing is towing the vehicle with two
wheels on the ground and two
wheels on a dolly.
Follow the tow vehicle
manufacturer’s instructions. See
your dealer or trailering professional
for additional advice and equipment
recommendations.
Caution
Use of a shield mounted in front
of the vehicle grille could restrict
airflow and cause damage to the
transmission. The repairs would
not be covered by the vehicle
warranty. If using a shield, only
use one that attaches to the
towing vehicle.
Dinghy Towing
Two-Wheel-Drive Vehicles
Caution
If the two-wheel-drive vehicle is
towed with all four wheels on the
ground, the drivetrain
components could be damaged.
The repairs would not be covered
by the vehicle warranty.
Two-wheel-drive vehicles should not
be towed with all four wheels on the
ground. Four-Wheel-Drive Vehicles
Only dinghy tow four-wheel-drive
vehicles with a two-speed transfer
case that have an N (Neutral) and a
Four-Wheel Drive Low (4 (
n) setting.
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Service and Maintenance 447
Caution (Continued)
approved by GM could damage
the vehicle, requiring expensive
repairs that are not covered by
the vehicle warranty.
The Tire Rotation and Required
Services are the responsibility of the
vehicle owner. It is recommended to
have your dealer perform these
services every 12 000 km/7,500 mi.
Proper vehicle maintenance helps to
keep the vehicle in good working
condition, improves fuel economy,
and reduces vehicle emissions.
Because of the way people use
vehicles, maintenance needs vary.
There may need to be more
frequent checks and services. The
Additional Required Services -
Normal are for vehicles that:
. Carry passengers and cargo
within recommended limits on
the Tire and Loading Information
label. See Vehicle Load Limits
0 248. .
Are driven on reasonable road
surfaces within legal driving
limits.
. Use the recommended fuel. See
Fuel 0299.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart.
The Additional Required Services -
Severe are for vehicles that are:
. Mainly driven in heavy city traffic
in hot weather
. Mainly driven in hilly or
mountainous terrain
. Frequently towing a trailer
. Used for high speed or
competitive driving
. Used for taxi, police, or delivery
service
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause
serious injury. Perform
maintenance work only if the
required information, proper tools,
and equipment are available.
If they are not, see your dealer to
have a trained technician do the
work. See Doing Your Own
Service Work 0344.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
498 Index
Maintenance Schedule (cont'd)Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . . . 456
Transfer Case . . . . . . . . . . . . . . . . 272
Malfunction Indicator Lamp . . . . . 150
Manual Mirrors . . . . . . . . . . . . . . . . . . 47
Manual Mode . . . . . . . . . . . . . . . . . . . 268
Manual Windows . . . . . . . . . . . . . . . . 52
Media Avoiding Untrusted Devices . . 195
Memory Features . . . . . . . . . . . . . . . . 13
Memory Seats . . . . . . . . . . . . . . . . . . . 62
Messages Engine Power . . . . . . . . . . . . . . . . 164
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 164
Vehicle Speed . . . . . . . . . . . . . . . . 164
Mirrors Automatic Dimming . . . . . . . . . . . . . 50
Automatic Dimming
Rearview . . . . . . . . . . . . . . . . . . . . . . 52
Blind Spot . . . . . . . . . . . . . . . . . . . . . . 50
Convex . . . . . . . . . . . . . . . . . . . . . . . . . 47
Folding . . . . . . . . . . . . . . . . . . . . . . . . . 49
Heated . . . . . . . . . . . . . . . . . . . . . . . . . 50
Manual . . . . . . . . . . . . . . . . . . . . . . . . . 47
Manual Rearview . . . . . . . . . . . . . . . 52
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Tilt in Reverse . . . . . . . . . . . . . . . . . . 51 Mirrors (cont'd)
Trailer Tow . . . . . . . . . . . . . . . . . . . . . . 48
Mirrors, Interior Rearview . . . . . . . . 51
Monitor System, Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 399
Multi-band Antenna . . . . . . . . . . . . . 194
N
Navigation OnStar . . . . . . . . . . . . . . . . . . . . . . . 481
New Vehicle Break-In . . . . . . . . . . . 255
Noise Control System . . . . . . . . . . 373
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . 142 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Off-Road . . . . . . . . . . . . . . . . . . . . . . . 239 Driving . . . . . . . . . . . . . . . . . . . . . . . . 239
Recovery . . . . . . . . . . . . . . . . . . . . . 238
Oil
Engine . . . . . . . . . . . . . . . . . . . . . . . . 350
Engine Oil Life System . . . . . . . 353
Engine Oil Pressure Gauge . . . 143
Pressure Light . . . . . . . . . . . . . . . . 156
Older Children, Restraints . . . . . . . 92
Online Owner Center . . . . . . . . . . . 468
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . 478
OnStar Additional Information . . . . . . . . . . . . . . . . . . . . 485 OnStar Connections . . . . . . . . . . . . 482
OnStar Diagnostics . . . . . . . . . . . . . 484
OnStar Emergency . . . . . . . . . . . . . 480
OnStar Navigation . . . . . . . . . . . . . . 481
OnStar Overview . . . . . . . . . . . . . . . 479
OnStar Security . . . . . . . . . . . . . . . . 481
Operating Mode
Overheated EngineProtection . . . . . . . . . . . . . . . . . . . 364
Operation Fog Lamps . . . . . . . . . . . . . . . . . . . 181
Ordering Service Publications . . . . . . . . . . 474
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . 133
Overheated Engine
Protection Operating Mode . . . . 364
Overheating, Engine . . . . . . . . . . . . 363
Overview . . . . . . . . . . . . . . . . . . . . . . . 188
P
Park Shifting Into . . . . . . . . . . . . . . . . . . . 262
Shifting Out of . . . . . . . . . . . . . . . . 263
Parking Brake . . . . . . . . . . . . . . . . . . . . . . . . . 281
Brake and P (Park)
Mechanism Check . . . . . . . . . . 375

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
502 Index
Towing (cont'd)Trailer . . . . . . . . . . . . . . . . . . . . . . . . 307
Trailer Sway Control (TSC) . . . 334
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 430
Traction Control System (TCS)/StabiliTrak Light . . . . . . . . . . . . . 155
Off Light . . . . . . . . . . . . . . . . . . . . . . 154
Traction Control/Electronic
Stability Control . . . . . . . . . . . . . . . 282
Trademarks and License Agreements . . . . . . . . . . . . . . . . . . . 218
Trailer Sway Control (TSC) . . . . . . . . . . 334
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 48
Towing . . . . . . . . . . . . . . . . . . . . . . . . 307
Transfer Case . . . . . . . . . . . . . . . . . . 272
Transmission Automatic . . . . . . . . . . . . . . . . . . . . . 265
Fluid, Automatic . . . . . . . . . 354, 357
Temperature Gauge . . . . . . . . . . 145
Transportation Program, Courtesy . . . . . . . . . . . . . . . . . . . . . . 471
Trip Odometer . . . . . . . . . . . . . . . . . . 142
Truck-Camper Loading Information . . . . . . . . . . . . . . . . . . . . 253
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . . . 181 Turn Signal
Bulb Replacement . . . . . . . . . . . . 378
U
Uniform Tire Quality Grading . . . 410
Universal Remote System . . . . . . 172Operation . . . . . . . . . . . . . . . . . . . . . 174
Programming . . . . . . . . . . . . . . . . . 172
Updates Software . . . . . . . . . . . . . . . . . . . . . . 189
USB Port . . . . . . . . . . . . . . . . . . . . . . . 197
Using This Manual . . . . . . . . . . . . . . . . 2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 44
Canadian Owners . . . . . . . . . . . . . . . 2
Control . . . . . . . . . . . . . . . . . . . . . . . 236
Identification Number (VIN) . . . 460
Load Limits . . . . . . . . . . . . . . . . . . . 248
Messages . . . . . . . . . . . . . . . . . . . . 164
Personalization . . . . . . . . . . . . . . . 165
Remote Start . . . . . . . . . . . . . . . . . . . 39
Security . . . . . . . . . . . . . . . . . . . . . . . . 44
Speed Messages . . . . . . . . . . . . . 164
Towing . . . . . . . . . . . . . . . . . . . . . . . . 430
Vehicle Ahead Indicator . . . . . . . . 154 Vehicle Care
Tire Pressure . . . . . . . . . . . . . . . . . 397
Vehicle Data Recording and Privacy . . . . . . . . . . . . . . . . . . . . . . . . 477
Ventilation, Air . . . . . . . . . . . . . . . . . . 231
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Voice Recognition . . . . . . . . . . . . . . 205
Voltage Devices and Wiring . . . . 380
Voltmeter Gauge . . . . . . . . . . . . . . . 145
W
Warning Brake System Light . . . . . . . . . . . 152
Caution and Danger . . . . . . . . . . . . . 3
Lane Departure (LDW) . . . . . . . 295
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . 137
Warnings Hazard Flashers . . . . . . . . . . . . . . 180
Washer Fluid . . . . . . . . . . . . . . . . . . . 366
Wheels Alignment and Tire Balance . . .411
Different Size . . . . . . . . . . . . . . . . . 409
Replacement . . . . . . . . . . . . . . . . . 412
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 407
Where to Put the Restraint . . . . . . 98
Wi-Fi . . . . . . . . . . . . . . . . . . . . . . . . . . . 482