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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 371
Engine Compartment
Fuse Block
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
The engine compartment fuse block
is in the engine compartment, on
the passenger side of the vehicle for
1500 and driver side of vehicle for
2500/3500.
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 end cap.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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374 Vehicle Care
FusesUsage
76 Electric RNG BDS
78 Engine control module
79 Auxiliary battery
80 Cabin cooling pump
81 Trailer stop/turn lamp right
82 TIM
83 FTZM
84 Trailer brake
85 ENG
86 Engine control module
87 Injector B even
88 O2 B sensor
89 O2 A sensor
90 Injector A odd
91 Engine control module throttle
control
92 Cool fan clutch Relays
Usage
5 Headlamp
18 DC/AC inverter
23 Rear window defogger
35 Parking lamp
36 Run/Crank
43 Second fuel pump
59 A/C clutch
64 Starter Motor (LD & HD DSL) / Cool
Fan Clutch
(HD Gas)
70 Starter Pinion (LD) / Starter Motor
(HD Gas)
77 PowertrainInstrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
Pull off the cover to access the fuse
block. A fuse puller is available in
the left instrument panel end cap.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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376 Vehicle Care
RelaysUsage
K5 MFEG minor 2
K6 MFEG major 2
K7 Anti-theft
K8 –
Instrument Panel Fuse
Block (Right)
The right instrument panel fuse
block access door is on the
passenger side edge of the
instrument panel. Pull off the cover to access the front
of the fuse block.
To access the back of the fuse
block:
1. Push the tab at the top of fuse
block down.
2. Pull the top of the fuse block outward.
3. Reverse Steps 1–2 to reinstall.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 401
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. Never exceed the winter
tires’maximum speed capability
when using winter tires with a
lower speed rating.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System 0389.
The Tire and Loading
Information label indicates the
original equipment tires on the vehicle. See
Vehicle Load Limits
0 200 for the label location and
more information about the Tire
and Loading Information label.
Different Size Tires and
Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
(Continued)
Warning (Continued)
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires 0399 and
Accessories and Modifications
0 329.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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406 Vehicle Care
{Warning
Lifting a vehicle and getting under
it to do maintenance or repairs is
dangerous without the
appropriate safety equipment and
training. If a jack is provided with
the vehicle, it is designed only for
changing a flat tire. If it is used for
anything else, you or others could
be badly injured or killed if the
vehicle slips off the jack. If a jack
is provided with the vehicle, only
use it for changing a flat tire.
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place, well off the road,
if possible. Turn on the hazard
warning flashers. See Hazard
Warning Flashers 0169.
{Warning
Changing a tire can be
dangerous. The vehicle can slip
off the jack and roll over or fall
causing injury or death. Find a
level place to change the tire. To
help prevent the vehicle from
moving:
1. Set the parking brake firmly.
2. Put the shift lever inP (Park).
3. For vehicles with four-wheel drive with an N (Neutral)
transfer case position, be
sure the transfer case is in a
drive gear —not in
N (Neutral).
4. Turn off the engine and do not restart while the vehicle
is raised.
5. Do not allow passengers to remain in the vehicle.
(Continued)
Warning (Continued)
6. Place wheel blocks,if equipped, on both sides of
the tire at the opposite
corner of the tire being
changed.
When the vehicle has a flat tire (2),
use the following example as a
guide to assist in the placement of
the wheel blocks (1), if equipped.
1. Wheel Block (If Equipped)
2. Flat Tire
The following information explains
how to use the jack and change
a tire.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 407
Tire Changing
Removing the Spare Tire and
Tools
1. Jack
2. Jack Knob
3. Tool Kit
4. Wing Nut Retaining Tool Kit
5. Wheel Blocks
6. Wing Nut Retaining WheelBlocks
The equipment is under the second
row seats, if equipped, or behind the
front row seats on regular cab
models. 1. Turn the knob on the jack
counterclockwise to lower the
jack head to release the jack
from its holder.
2. Turn the wing nut counterclockwise to remove the
wheel blocks and the wheel
block retainer.
3. Turn the wing nut used to retain the storage bag and
tools counterclockwise to
remove it.
Use the jack handle extensions and
the wheel wrench to remove the
underbody-mounted spare tire.
1. Spare Tire (Valve Stem Pointed Down)
2. Tire/Wheel Retainer
3. Hoist Cable
4. Hoist Assembly
5. Hoist Shaft
6. Jack Handle Extensions
7. Wheel Wrench
8. Spare Tire Lock (If Equipped)
9. Hoist Shaft Access Hole
10. Hoist End of Extension Tool
11. Spare Tire Cable (If Equipped)
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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408 Vehicle Care
1. Open the spare tire lock coveron the bumper and use the
ignition key to remove the
spare tire lock (8). To remove
the spare tire lock, insert the
ignition key, turn, and pull
straight out.
2. Assemble the wheel wrench (7)
and the two jack handle
extensions (6), as shown.
3. If the vehicle is equipped with aspare tire cable disconnect the
cable from the attachment on
the frame by unclipping it from
the frame attachment bracket.
4. Insert the hoist end (openend) (10) of the extension
through the hole (9) in the rear
bumper.
Do not use the chiseled end of
the wheel wrench.
Be sure the hoist end of the
extension (10) connects to the
hoist shaft. The ribbed square
end of the extension is used to
lower the spare tire.
5. Turn the wheel wrench counterclockwise to lower the
spare tire to the ground.
Continue to turn the wheel
wrench until the spare tire can
be pulled out from under the
vehicle.
6. Pull the spare tire out from under the vehicle.
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Vehicle Care 409
7. Tilt the tire toward the vehiclewith some slack in the cable to
access the tire/wheel retainer.
1500 Models
All Other Models
Tilt the retainer and pull it
through the center of the wheel
along with the cable and
spring.
8. Put the spare tire near the flat tire.
9. If equipped with a spare tirecable remove the cable from
the spare tire by passing the
clip through the looped end of
the cable.
Removing the Flat Tire and
Installing the Spare Tire
Use the following pictures and
instructions to remove the flat tire
and raise the vehicle.
1. Jack
2. Wheel Blocks
3. Jack Handle
4. Jack Handle Extensions
5. Wheel Wrench