2001 CHEVROLET C3500 HD light

6-60 Headlamps
The headlamp wiring is protected by an internal circuit
breaker. An electrical overload will cause the lamps
to go on and off, or in some cases to remain off.
If this happens, have your headlamp wiring checked
right away.
Windshield Wipers
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop until the motor cools.
If the overload is caused by some electrical problem
and not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers protect the power windows and other
power accessories. When the current load is too heavy,
the circuit breaker opens and closes, protecting the
circuit until the problem is fixed or goes away.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of fires caused by electrical problems.
Look at the silver
-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical size
and rating.
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace it as soon as you can.

6-62
Fuse/Circuit
BreakerUsage
4 Instrument Cluster, DRL Relay,
Lamp Switch, Keyless Entry, Low
Coolant Module, Illuminated Entry
Module, DRAC (Diesel Engine)
5 Not Used
6 Cruise Control
7 Auxiliary Power Outlet
8 Crank
9 License Lamp, Parking Lamps,
Taillamps, Roof Marker
Lamps, Front Sidemarkers,
Door Switch Illumination,
Headlamp Switch Illumination
10 Not Used
11 Wiper Motor, Washer Pump
12 A/C, A/C Blower,
High Blower Relay
13 Power Amp, Cigarette Lighter,
Door Lock RelayFuse/Circuit
BreakerUsage
14 Cluster, Comfort Controls,
Instrument Switches, Radio
Illumination, Chime Module
15 DRL Relay
16 Front and Rear Turn Signals,
Back
-Up Lamps
17 Radio (Ignition)
18 4WAL/VCM, ABS, Cruise Control
19 Radio (Battery)
20 PRNDL, Automatic Transmission,
Speedometer, Check Gages
Warning Light
21 Security/Steering
22 Not Used
23 Not Used
24 TP2 Relay (Gasoline Engine)
A Power Door Lock, Keyless
Entry Module
B Power Windows

6-64
Name Usage
Horn Relay Horn
ECM
-B Fuel Pump, PCM/VCM
RR DEFOG Not Used
IGN
-E A/C Compressor Relay,
Dual Tanks
Blank Not Used
Blank Not Used
Blank Not Used
HORN Horn, Underhood Lamps
AUX FAN Not Used
ECM
-1 Injectors, PCM/VCM, Fuel
Solenoid (Diesel Engine) Fuel
Control Module (Diesel Engine)
HTD ST
-FR Not Used
Blank Not Used
Blank Not Used
A/C Air Conditioning
PTO PTO RelayName Usage
ENG
-1 Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast
Solenoid, MAF, Heated O
2,
Fuel Heater (Diesel Engine),
Water Sensor (Diesel Engine),
Boost Solenoid (Diesel Engine),
EPR (Diesel Engine)
HTD ST
-RR Not Used
Blank Not Used
Diode Not Used
LIGHTING Headlamp and Panel Dimmer
Switch, Fog and Courtesy Fuses
BATT Battery, Fuse Block Busbar
IGN A Ignition Switch
IGN B Ignition Switch
ABS Anti
-Lock Brake Module
BLOWER High Blower Relay
STOP/HAZ Stoplamps
HEATED
SEATSNot Used

7-46 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages are
working properly. Look for any other loose or damaged
safety belt system parts. If you see anything that might
keep a safety belt system from doing its job, have it
repaired. Have any torn or frayed safety belts replaced.
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.
Spare Tire Check
At least twice a year, after the monthly inflation check
of the spare tire determines that the spare is inflated to
the correct tire inflation pressure, make sure that the
spare tire is stored securely.Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an indicator located on the air cleaner
in the engine compartment that lets you know when the
air cleaner filter is dirty and needs to be changed. Check
indicator at least twice a year or when your engine oil is
changed, whichever occurs first. See ªAir Cleanerº in
the Index for more information. Inspect your air cleaner
filter restriction indicator more often if the vehicle is
used in dusty areas or under off road conditions.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. See ªRecommended Fluids and Lubricantsº
in the Index.
Manual Transmission Check
Check the transmission fluid level; add if needed. See
ªManual Transmission Fluidº in the Index. Check for
leaks. A fluid leak is the only reason for fluid loss. Have
the system inspected and repaired if needed.

8-7
Chevrolet offers Courtesy Transportation for customers
needing warranty service. Courtesy Transportation will
be offered in conjunction with the coverage provided by
the Bumper
-to-Bumper New Vehicle Limited Warranty
to eligible purchasers of 2001 Chevrolet passenger cars
and light duty trucks. (Please see your selling dealer
for details.)
Courtesy Care is available to retail and retail lease
customers operating 2001 and newer Chevrolet vehicles
for a period of 3 years/36,000 miles (60 000 km),
whichever occurs first. All Courtesy Care services must
be pre
-arranged by Chevrolet Roadside or dealer
service management.
Basic Care and Courtesy Care are not part of or
included in the coverage provided by the New Vehicle
Limited Warranty. Chevrolet reserves the right to
modify or discontinue Basic Care and Courtesy Care
at any time.
The Roadside Assistance Center uses companies
that will provide you with quality and priority service.
When roadside services are required, our advisors will
explain any payment obligations that may be incurred
for utilizing outside services.For prompt assistance when calling, please have the
following available to give to the advisor:

Vehicle Identification Number (VIN)

License plate number

Vehicle color

Vehicle location

Telephone number where you can be reached

Vehicle mileage

Description of problem
Canadian Roadside Assistance
Vehicles purchased in Canada have an extensive
Roadside Assistance program accessible from anywhere
in Canada or the United States. Please refer to the
separate brochure provided by the dealer or call
1
-800-268-6800 for emergency services.

8-13
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