Page 329 of 433

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
328 Vehicle Care
To replace one of these bulbs:
1. Remove the two screws and lift off thelamp assembly.
2. Turn the bulb socket counterclockwise and pull it straight out.
3. Pull the bulb straight out from the socket.
License Plate Lamp
To replace the bulb:
1. Reach behind the rear bumper and locate the bulb.
2. Turn the bulb socket counterclockwise and pull the bulb straight out of the
socket.
3. Replace the bulb and reverse Step 2 toreinstall.
Electrical System
Electrical System Overload
The vehicle has fuses to protect against an
electrical system overload. Fuses also protect
power devices in the vehicle.
Replace a bad fuse with a new one of the
identical size and rating.
If there is a problem on the road and a fuse
needs to be replaced, there are some spare
fuses and a fuse puller in the left
instrument panel fuse block. The
same amperage fuse can also be borrowed. Choose some feature of the vehicle that is
not needed to use and replace it as soon as
possible.
Headlamp Wiring
An electrical overload may cause the lamps
to go on and off, or in some cases to
remain off. Have the headlamp wiring
checked right away if the lamps go on and
off or remain off.
Windshield Wipers
If the wiper motor overheats due to heavy
snow or ice, the windshield wipers will stop
until the motor cools and will then restart.
Although the circuit is protected from
electrical overload, overload due to heavy
snow or ice may cause wiper linkage
damage. Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an electrical
problem and not snow or ice, be sure to get
it fixed.
Page 330 of 433

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 329
Fuses and Circuit Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit breakers.
This greatly reduces the chance of damage
caused by electrical problems.
{Danger
Fuses and circuit breakers are marked
with their ampere rating. Do not exceed
the specified amperage rating when
replacing fuses and circuit breakers. Use
of an oversized fuse or circuit breaker can
result in a vehicle fire. You and others
could be seriously injured or killed.
{Warning
Installation or use of fuses that do not
meet GM’s original fuse specifications is
dangerous. The fuses could fail, and result(Continued)
Warning (Continued)
in a fire. You or others could be injured
or killed, and the vehicle could be
damaged.
See Accessories and Modifications 0302 and
General Information 0301.
To check a fuse, look at the silver-colored
band inside the fuse. If the band is broken
or melted, replace the fuse. Be sure to
replace a bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another fuse
location, if a fuse goes out. Replace the fuse
as soon as possible.
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 driver side of
vehicle.
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.
Page 331 of 433
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
330 Vehicle Care
FusesUsage
1 High-beam left
2 High-beam right Fuses
Usage
3 Headlamp left
4 Headlamp right Fuses
Usage
6 –
7 –
8 Fog lamp
9 –
10 –
11 Police upfitter
12 –
13 Washer front
14 Washer rear 15 –
16 –
17 IECL 1
19 DC/AC inverter
20 IECR 2 (LD) / EBCM2 (HD)
21 –
22 IECL 2
24 EBCM 1 25 –
26 –
Page 332 of 433

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 331
FusesUsage
27 Horn
28 –
29 –
30 –
31 –
32 Rear window defogger
33 Heated mirror
34 Parking lamp left 37 –
38 –
39 –
40 Misc ignition 41 Trailer parking lamp
42 Park lamp right
44 –
45 –
46 Engine control module ignition
47 Transmission control module ignition Fuses
Usage
48 –
49 Transmission control module
50 A/C clutch 51 Transfer case control module
52 Front wiper
53 Center high-mounted stop lamp
54 Trailer reverse lamp 55 Trailer back-up lamp
56 SADS 57 TTPM/SBZA
58 Starter motor (LD & HD DSL)
60 Active fuel management 1
61 VES
62 Integrated chassis control module/CVS
63 Trailer battery Fuses
Usage
65 Auxiliary underhood electrical center
66 Cooling fan motor left 67 Active fuel management 2
68 –
69 Starter Pinion (LD) / Starter Motor (HD Gas)
71 Cooling fan
72 Cooling fan right/lower
73 Trailer stop/turn lamp left
74 Trailer Interface Module 1
75 DEFC
76 Electric RNG BDS
78 Engine control module
79 Auxiliary battery
80 Cabin cooling pump 81 Trailer stop/turn lamp right
Page 333 of 433
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
332 Vehicle Care
FusesUsage
82 Trailer Interface Module 2
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/ Aeroshutter Relays
Usage
5 Headlamp
18 DC/AC inverter
23 Rear window defogger
35 Parking lamp
36 Run/Crank
43 –
59 A/C clutch
64 Starter Motor (LD & HD DSL)
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.
Page 334 of 433
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 333
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
F1 Rear heated seats left/right Fuses
Usage
F3 –
F4 –
F5 Spare/MFEG
F6 Heated and ventilated seats left/right
F8 –
F9 Passive entry passive start/ Spare
F10 –
F11 –
F12 Passenger power seat
F13 Export power take off/ Special equipment option 1
F14 –
F15 –
F16 AMP F17 –
F18 –
F20 Endgate F22 Rear sliding window
F23 – Fuses
Usage
F24 –
F25 –
F26 –
F27 –
Circuit
Breakers Usage
CB1 –
Relays Usage
K1 Rear sliding window open
K2 Rear sliding window close
K3 MFEG major 1
K4 MFEG minor 1 K5 MFEG minor 2
K6 MFEG major 2 K7 –
K8 –
Page 335 of 433
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
334 Vehicle Care
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 fuseblock down.
2. Pull the top of the fuse block outward.
3. Reverse Steps 1–2 to reinstall.
Page 336 of 433

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 335
Back
The vehicle may not be equipped with all of
the fuses, relays, and features shown. Fuses Usage
F1 Right doors
F2 Left doors
F3 Universal garage door opener
F4 –
F5 –
F6 Front blower
F8 Lumbar switch
F10 Body control module 6/ Body control module 7
F11 Seat/Column lock module
F12 Body control module 3/ Body control module 5
F14 Mirrors/Windows module F17 Steering wheel controls
F18 Video processing module/ Obstacle detection
F19 DLIS
F20 Ventilated seats F21 NOT R/C
F22 Heated steering wheel Fuses Usage
F23 MISC R/C
F24 Instrument panel cluster ignition/Overhead
F25 Heating, ventilation, and air conditioning ignition/
Heating, ventilation, and
air conditioning auxiliary
F26 USB ports/Special equipment option retained
accessory power
F27 Accessory power outlet/ retained accessory power
F28 Accessory power outlet/ Battery
F30 Sensing and diagnostic module/Parking brake
F31 Body control module 4
F32 Special equipment option/ Data link connection
F33 Body control module 8
F34 Cargo lamp
F40 CGM F41 Infotainment 1