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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
276 Vehicle Care
D. Open the front door, tightenthe nut from the inside of
the door, and install the
rubber cap.
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
1. Turn Signal Lamp
2. Taillamp/Stoplamp
3. Back-Up Lamp
4. Lens
1. Loosen the screws and remove the lens.
2. Loosen the bulb by turning it counterclockwise while
pressing on it.
3. To install the lights, follow the removal procedure in reverse.
License Plate Lamp
1. Bulb
2. Lens
3. Screw
4. Cover
1. Loosen the screws and removethe cover.
2. Remove the lens.
3. Loosen the bulb by turning it counterclockwise while
pressing on it.
4. To install the lights, follow the removal procedure in reverse.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 277
Interior Lamps
1. Remove the lens and pull outthe bulb.
2. To install the lights, follow the removal procedure in reverse.
Electrical System
Electrical System
Overload
Electrical System
Following the after-delivery service,
it is the owner's responsibility to
check all wiring periodically for
cracked, chafed or oil-soaked
insulation and maintain it in a clean
and tight condition to ensure
satisfactory operation of the
electrical system.
Replacing the Fuses and Relays
Your vehicle is equipped with fuses
and fusible links to protect your
electrical wiring and equipment in
case of electrical overload.
When the lights do not come on or
flash, or the equipment in the
electrical system does not operate,
check to see if a fuse has blown. Fuses :
In case of an electrical
overload, the fuse will blow and stop
the flow of current in the circuit
before electrical components
become damaged.
The cause of the circuit overload
must be identified and corrected
before the blown fuse is replaced,
or else the new fuse will also blow.
Since different circuits handle
different amounts of current, fuses
of various ampere ratings are used.
Be sure to replace a blown fuse with
a fuse of the correct rating.
To know if a fuse is blown or not,
remove the suspected fuse and look
at the wire for a break. If the wire is
broken, replace the fuse with one of
equal amperage rating.
The amperage rating of each fuse is
molded in its head.
Fuses are installed in the fuse
panel.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 281
No. Description Rating17 IGNITION 2 10A
18 IGNITION 1 10A
19 TRANSMISSION 5A
20 ECM 10A
21 METER 10A
22 ECU (BATT) 10A
23 MIRROR 10A
24 AUDIO, ACC 15A
25 HORN 15A
26 TURN, HAZARD 15A
27 TAIL LAMPS 10A
28 ILLUMINATIONS 10A
29 CORNERING LAMPS 10A
30 AIR CONDITIONER 10A
31 – –
32 – –
33 – –
34 – – No. Description Rating
B-1 BACK UP LIGHT 10A
B-2 BACK UP LIGHT (SERVICE) 10A
B-3 AUDIO REVERSE MUTE 10A
B-4 PTO 10A
D-1 CIGAR 20A
D-2 ACCESSORIES SOCKET 15A
D-3 POWER SOURCE 20A
D-4 SPARE 5A
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
282 Vehicle Care
Relay LocationRelay locations:
No. Description
1 STOP LAMP
2 DAYTIME RUNNING LAMP
3 KEY ON
4 PARKING/NEUTRAL
5 –
6 WIPER MAIN
7 HORN
8 WIPER HI LO
9 TRAILER BRAKE
10 POWER WINDOW
11 BACK UP LAMP
12 POWER WINDOW
13 HEAD LAMP LO
14 VACUUM PUMP
15 HEAD LAMP HI
16 TAIL LAMP
17 CIGAR LIGHTER
18 CORNERING LAMP
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 283
No. Description19 POWER ACC
20 BLOWER MOTOR Fuse and Relay Location
–Cab Exterior
Fuse and Relay Location
Fuse locations (2): No. Description Rating
1 MARKER LIGHT 20A
2 TAIL MAIN 20A
3 ECM MAIN 15A
4 SCR 20A No. Description Rating
5 PM SENSOR 15A
6 RR DOME LIGHT 15A
7 CONDENSER FAN 20A
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
284 Vehicle Care
No. Description Rating8 A/C 10A
Relay locations (1): No. Description
1 STARTER
2 ECM MAIN
3 NOX & DEF SENSOR
4 A/C COMPRESSOR
5 CONDENSER FAN
6 RR DOME LIGHT
7 SCR HEATER VALVE
8 MARKER LIGHT
9 –
10 –
11 FUEL HEATER When Slow-blow Fuses Blow Out
Slow-blow fuses protect the
electrical circuits, and they are
installed so that they can be quickly
replaced if there is a malfunction.
If an overload exists in the circuit
from the battery, the slow-blow fuse
will blow out before the wiring
harness is damaged to protect the
electrical circuitry. InspectionWhen the headlights and other
devices in the electrical system do
not work, but there is no problem
with the fuses, check the
slow-blow fuse.
The slow-blow fuse is blown if it
looks like the illustration.
Immediately contact the nearest
dealer.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 289
Recommended replacement tire for Greenhouse Gas (GHG) emissions
Tire sizeTire makerTire name Rolling
resistance
LT215/85R16E BRIDGESTONE CORPORATION
M779AZ LRRA
THE YOKOHAMA RUBBER CO., LTD. TY213B LRRA
225/70R19.5F BRIDGESTONE CORPORATION
M895Z LRRA
SUMITOMO RUBBER INDUSTRIES, LTD. (DUNLOP) SP688 LRRA
If the original equipment tires are
low rolling tires, it is recommended
to use the LRRA tires shown in the
above table.
Refer to the emission control
identifiers on Greenhouse Gas
(GHG) emission plate for your
original equipment tires. Also,
please refer to “VIN, Weight Rating,
and Greenhouse Gas (GHG)
Emissions Plate” for the location of
the Greenhouse Gas (GHG)
emission plate. See Vehicle
Identification Number (VIN) 0343. Wheel Replacement
Recommendations
Wheels must be replaced if they
become damaged (for example:
bent, heavily rusted, leak air) or if
wheel nuts often become loose. Do
not use bent wheels that have been
straightened and do not use inner
tubes in leaking wheels which are
designed for tubeless tires. Such
wheels may have structural damage
and could fail without warning.
When replacing wheels for any
reason, the new wheels should be
equal in load capacity, diameter, width, offset and mounting types to
those originally installed in your
vehicle.
A wheel of the wrong size or type
may adversely affect wheel and
bearing life, brake cooling,
speedometer/odometer calibration,
stopping ability, headlight aim,
bumper height, vehicle ground
clearance and tire or tire chain
clearance on the body and chassis.
Replacement with "used" wheels is
not advised. They may have been
subjected to harsh treatment or very
high mileage and could fail without
warning.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Vehicle Care 303
the negative (–) terminal which
is grounded (attached to the
engine block, or frame rail).
2. Position the vehicle with the good (charged) battery so that
the booster (jumper) cables will
reach. But never let the
vehicles touch. Also, be sure
the booster cables to be used
do not have loose or missing
insulation.
3. In both vehicles, turn off the ignition (engine control) switch
and all lights and accessories
except the hazard flasher or
any lights needed for the work
area. In both vehicles, apply
the parking brake firmly and
move the selector lever to the
"P" position.
4. Unlatch the latches (1) and
remove the battery cover (2)
and connect the jumper cables
in the numbered sequence in
the drawing below. Make sure
the cable clamps do not touch
any other metal parts. Make sure the cables are not
on or near pulleys, fans or
other parts that will move when
the engine is started.
When it is difficult to start the
engine in a cold area, first start
the engine of the vehicle with
the booster battery or batteries
and a few minutes after that
start the engine of the disabled
vehicle.