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In Brief 11
1. Air Flow Direction ControlLever. See Air Vents0118.
2. Exterior Lamp Controls 092.
Cruise Control Set Switch. See
Cruise Control 0202.
3. Windshield Wiper and Windshield Washer Switch.
See Windshield Wiper/Washer
0 66.
Exhaust Brake Switch. See
Exhaust Brake 0201.
4. Heater and Manual Air Conditioner. See Climate
Control Systems 0115.
5. Radio with CD/USB. See AM-FM Radio 097.
6. Small Article Storage Pockets. See Instrument Panel Storage
0 55.
7. Windshield Washer Fluid Tank. See Washer Fluid 0241.
8. Glove Box 055.
9. Relay Box. See Electrical
System Overload 0264.
10. Cupholders 056. 11. Hook. See
Shopping Bag
Hooks 058.
12. Card Holder. See Instrument
Panel Storage 055.
13. Cigarette Lighter 067.
14. Accessory Power Outlet. See Power Outlets 067.
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Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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264 Vehicle Care
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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Vehicle Care 265
The Location of Fuses and Relays
The fuses (3) and relays (2) are
located in the lower part of the
instrument panel in the center and
in the left rear of the cab.
The cover (1) must be opened in
order to carry out inspection and
replacement. In addition, the
cover (1) of the relay box at the left
rear of the cab must also be opened
at this time.
If you should spill water or a
beverage on the cover, wipe it off
before opening the cover.
The area around the cover may get
warm when the vehicle is being
driven, but this is not abnormal.Replacing Fuses
1. Before replacing fuses, firmly apply the parking brake, move
the selector lever to the
P (Park) position, and turn the
engine control switch to the
LOCK position.
2. The fuse puller is stored in the fuse box inside the cab. Place
the fuse puller on the fuse and
pull it out.
3. If the fuse appears asshown (2), the fuse is blown.
Replace with a spare fuse (1).
Spare fuses are stored in the
fuse box inside the cab.
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266 Vehicle Care
{Warning
Always use fuses specified for the
vehicle. Using fuses with a rating
other than that specified, or using
wire or tin foil, etc., could result in
fire or damage.
If the new fuses blow right away
and the cause is unknown,
contact your dealer.
Do not inspect or replace fuses
when the starter switch is in the
ON position. Doing so may lead
to an accident.
When inspecting fuses, be sure to
park the vehicle on flat, level
ground and apply chocks to the
wheels.Replacing Relays
Before replacing the relays, contact
the nearest dealer.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
It is not necessary to open or close
the cover unless trouble is found.
The relay box structure makes it
difficult for water to enter. If you
should spill water or a beverage of
the cover, however, wipe it off
before opening the cover.
The area around the cover will get
warm when the vehicle is being
driven, but this is not abnormal.
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Vehicle Care 267
Fuse and Relay Location–Cab InteriorFuse locations:
No. Description Rating
1 RR P / WINDOW 25A
2 – –
3 ROOM LAMP, AUDIO 10A
4 DOOR LOCK 15A
5 TRAILER BRAKE 15A
6 P/ WINDOW 25A
7 ABS 10A
8 WIPER 25A
9 H / LAMP LO (LH) 10A
10 LAMPS (BATT) 10A 11 H / LAMP LO (RH) 10A
12 BRAKE LAMPS 10A
13 STARTER 10A
14 H / LAMP HI (LH) 10A
15 H / LAMP HI (RH) 10A
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Vehicle Care 269
Relay LocationRelay locations:
No. Description
1 STOP LAMP
2 DAYTIME RUNNING LAMP
3 KEY ON
4 TCM
5 PARKING/NEUTRAL
6 WIPER MAIN
7 HORN
8 WIPER HI LO
9 TRAILER BRAKE
10 –/REAR POWER
WINDOW (if
equipped)
11 –/CHARGE (ENG
RUN) - Gasoline
12 POWER WINDOW
13 HEAD LAMP LO
14 VACUUM PUMP
15 HEAD LAMP HI
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270 Vehicle Care
No. Description16 TAIL LAMP
17 CIGAR LIGHTER
18 CORNERING LAMP
19 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 FUEL HEATER 15A
4 SCR 20A
5 PM SENSOR 15A No. Description Rating
6 RR DOME LIGHT 15A
7 CONDENSER FAN 20A
8 A/C 10A
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Vehicle Care 271
Relay locations (1):No. Description
1 STARTER
2 PM SENSOR
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.