2004 CHEVROLET SILVERADO battery

Heavy-DutyTrailer Wiring
Harness Package
Your pickup may be equipped with the eight-wire trailer
towing harness. This harness with a seven-pin
universal trailer connector is attached to a bracket on
the hitch platform.
* The Center High-Mounted Stoplamp (CHMSL) wire is
tied next to the trailer wiring harness for use with a
trailer, slide-in camper or cap.The eight-wire harness contains the following
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: CHMSL
Red: Battery Feed
Dark Blue: Trailer Brake
If your trailer is equipped with electric brakes, you can
get a jumper harness (electric trailer brake control)
with a trailer battery feed fuse from your dealer.
If you need to tow a light-duty trailer with a standard
four-way round pin connector you can also get an
adapter from your dealer.
4-96

Camper/Fifth-Wheel Trailer Wiring Package
The eight-wire camper harness is located under the
front edge of the pickup box on the driver’s side of the
vehicle, attached to the frame bracket. A connector
will have to be added to the wiring harness which
connects to the camper.
The eight-wire harness contains the following
camper/trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: Center High-Mounted
Stoplamp (CHMSL)
Red: Battery Feed
Dark Blue: Trailer BrakeIf your vehicle is equipped with the “Heavy-Duty
Trailering” option, please refer to “Heavy-Duty Trailer
Wiring Package” earlier in this section.
When the camper-wiring harness is ordered without the
heavy-duty trailering package, an eight-wire harness
with a seven-pin connector and separate CHMSL
connector are located at the rear of the vehicle and are
tied to the vehicle’s frame.
4-97

Instrument Panel Jumper Wiring Harness
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from
your dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
4-98

Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that you
may choose to add, such as a slide-in camper.
If your vehicle has this
provision, this relay will be
located on the passenger’s
side of the vehicle, next
to the auxiliary battery.
When using this provision, connection should only be
made to the upper stud (A) of the relay. Do not
make connections to the lower stud (B) of the relay.
The auxiliary battery circuit is protected by a megafuse
located behind the auxiliary battery.
Be sure to follow the proper installation instructions
that are included with any electrical equipment that
you install.Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do
not use equipment that exceeds the maximum
amperage rating for the auxiliary battery provision.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
Power Take-Off (PTO)
Before using a PTO, if equipped, refer to the
manufacturer’s or installer’s instructions.
To engage a PTO on a vehicle with a manual
transmission do the following:
1. Hold the clutch pedal down.
2. Set the parking brake.
3. Shift the transmission into NEUTRAL (N).
4. Engage the PTO. Refer to the manufacturer’s
or installer’s for instructions on electrically
engaged PTOs.
5. For mobile operations, shift the transmission into
the gear you want, apply the regular brakes and
release the parking brake. For stationary operations,
leave the parking brake applied.
4-100

Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuel E-85 (85% Ethanol).................................5-8
Fuels in Foreign Countries...............................5-9
Filling Your Tank............................................5-9
Filling a Portable Fuel Container.....................5-11
Checking Things Under the Hood....................5-12
Hood Release..............................................5-12
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-20
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-27
Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30
Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34Engine Coolant.............................................5-35
Coolant Surge Tank Pressure Cap..................5-38
Engine Overheating.......................................5-38
Cooling System............................................5-41
Engine Fan Noise.........................................5-46
Power Steering Fluid.....................................5-46
Windshield Washer Fluid................................5-47
Brakes........................................................5-49
Battery........................................................5-52
Jump Starting...............................................5-53
All-Wheel Drive..............................................5-58
Rear Axle.......................................................5-59
Four-Wheel Drive............................................5-60
Noise Control System.....................................5-61
Tampering with Noise Control System
Prohibited.................................................5-61
Bulb Replacement..........................................5-63
Halogen Bulbs..............................................5-63
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-65
Roof Marker Lamps......................................5-66
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.......................................5-68
Section 5 Service and Appearance Care
5-1

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank. SeeEngine Coolant on
page 5-35.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. SeeEngine Oil on page 5-20.
E. Automatic Transmission Dipstick (If equipped).
SeeAutomatic Transmission Fluid (Except Allison
Transmission
®) on page 5-27orAutomatic
Transmission Fluid (Allison Transmission®)on
page 5-30.
F. Fan. SeeCooling System on page 5-41.
G. Engine Oil Fill. SeeEngine Oil on page 5-20.H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
I. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. SeeBrakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-123.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-47.
5-15

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank. SeeEngine Coolant on
page 5-35.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. SeeEngine Oil on page 5-20.
E. Automatic Transmission Dipstick (If Equipped).
SeeAutomatic Transmission Fluid (Except Allison
Transmission
®) on page 5-27orAutomatic
Transmission Fluid (Allison Transmission®)on
page 5-30.
F. Engine Oil Fill. SeeEngine Oil on page 5-20.
G. Fan. SeeCooling System on page 5-41.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
I. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. SeeBrakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-123.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-47.
5-17

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank. SeeEngine Coolant on
page 5-35.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. SeeEngine Oil on page 5-20.
E. Automatic Transmission Dipstick (If Equipped).
SeeAutomatic Transmission Fluid (Except Allison
Transmission
®) on page 5-27orAutomatic
Transmission Fluid (Allison Transmission®)on
page 5-30.
F. Engine Oil Fill. SeeEngine Oil on page 5-20.
G. Fan. SeeCooling System on page 5-41.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
I. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
J. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
K. Brake Fluid Reservoir. SeeBrakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-123.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-47.
5-19