2004 CHEVROLET SILVERADO wiring

Electrical System
Add-On Electrical Equipment
Notice:Don’t add anything electrical to your vehicle
unless you check with your dealer rst. Some
electrical equipment can damage your vehicle and
the damage wouldn’t be covered by your warranty.
Some add-on electrical equipment can keep other
components from working as they should.
Your vehicle has an air bag system. Before attempting
to add anything electrical to your vehicle, see
Servicing Your Air Bag-Equipped Vehicle on page 1-83.
Windshield Wiper Fuses
The windshield wiper motor is protected by an internal
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 xed.
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 xed 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 res 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.
5-123

Center Instrument Panel Fuse Block
The center instrument panel utility block is located
underneath the instrument panel, to the left of the
steering column.
Device Usage
SEO Special Equipment Option
TRAILER Trailer Brake Wiring
UPFIT Uptter (Not Used)
SL RIDERide Control
Harness Connection
HDLR 2 Headliner Wiring Connector
Device Usage
BODY Body Wiring Connector
DEFOG Rear Defogger Relay
HDLNR 1 Headliner Wiring Connector 1
SPARE RELAY Not Used
CB SEATDriver and Passenger Seat
Module Circuit Breaker
CB RT DOORRight Power Windows
Circuit Breaker
SPARE Not Used
INFOInfotainment
Harness Connection
5-126

*1— Gasoline Engine and Diesel Engine.
*2— Gasoline Engine; ECMRPV — Diesel Engine.
*3— Gasoline Engine; FUEL HT — Diesel Engine.
*4— Gasoline Engine; ECM I — Diesel Engine.
*5— IGN/EDU
Fuses Usage
GLOW PLUGDiesel Glow Plugs and Intake
Air Heater
CUST FEED Gasoline Accessory Power
STUD #1Auxiliary Power (Single
Battery and Diesels Only)/
Dual Battery (TP2) Do not
install fuse.
MBECMid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
BLOWER Front Climate Control Fan
LBECLeft Bussed Electrical
Center, Door Modules, Door
Locks, Auxiliary Power
Outlet — Rear Cargo Area
and Instrument Panel
Fuses Usage
STUD 2Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-Lock Brakes
VSES/ECAS Vehicle Stability
IGN A Ignition Power
IGN B Ignition Power
LBEC 1Left Bussed Electrical Center,
Left Doors, Truck Body
Controller, Flasher Module
TRL PARK Parking Lamps Trailer Wiring
RR PARKRight Rear Parking and
Sidemarker Lamps
LR PARKLeft Rear Parking and
Sidemarker Lamps
PARK LP Parking Lamps Relay
STARTER Starter Relay
INTPARK Interior Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller
Battery Feed
SUNROOF Sunroof
SEO B2 Off-Road Lamps
5-129

Fuses Usage
4WSVent Solenoid
Canister/Quadrasteer
Module Power
RR HVAC Not Used
AUX PWRAuxiliary Power
Outlet — Console
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster, Air
Conditioning Relay, Turn
Signal/Hazard Switch,
Starter Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window DefoggerFuses Usage
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
02B Oxygen Sensors
SIRSupplemental Inatable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running
Lamps (Relay)
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LT High Beam Headlamp-Left
LH HID Not Used
DRL Daytime Running Lamps
IPC/DICInstrument Panel Cluster/
Driver Information Center
HVAC/ECAS Climate Control Controller
CIG LTR Cigarette Lighter
HI HDLP-RT High Beam Headlamp-Right
HDLP-LOW Headlamp Low Beam Relay
A/C COMP Air Conditioning Compressor
5-130

H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-8
Headlamp High/Low-Beam Changer.................... 3-8
Headlamps....................................................5-63
Bulb Replacement.......................................5-63
Front Turn Signal, Sidemarker and Daytime
Running Lamps........................................5-65
Halogen Bulbs............................................5-63
Pickup Box Identication and Fender
Marker Lamps.........................................5-69
Roof Marker Lamps.....................................5-66
Headphones.................................................3-115
Heated Seats................................................... 1-5
Heating.........................................................3-30
Heavy-DutyTrailer Wiring Harness Package........4-96
Highway Hypnosis...........................................4-43
Hill and Mountain Roads..................................4-44
Hitches..........................................................4-88
Hood
Checking Things Under................................5-12
Release.....................................................5-12
Horn............................................................... 3-6
How to Add Coolant to the Coolant Surge Tank
for Gasoline Engines....................................5-43
How to Add Fluid............................5-30, 5-33, 5-34How to Check and Add Fluid............................5-35
How to Check Lubricant...................................5-59
How to Check Power Steering Fluid..................5-47
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-16
Hydraulic Clutch.............................................5-34
Hydroplaning..................................................4-39
I
If No Steam Is Coming From Your Engine..........5-40
If Steam Is Coming From Your Engine...............5-39
If the Light is Flashing.....................................3-49
If the Light Is On Steady.................................3-49
If You Are Caught in a Blizzard.........................4-48
If You Are Stuck in Sand, Mud, Ice or Snow.......4-50
If You Do Decide To Pull A Trailer.....................4-70
Ignition Positions.............................................2-23
Infants and Young Children, Restraints...............1-34
Ination - Tire Pressure...................................5-82
Instrument Panel
Cluster.......................................................3-34
Overview..................................................... 3-4
Instrument Panel Brightness Control..................3-18
Instrument Panel Fuse Block..........................5-124
Interior Lamps................................................3-18
8

Theft-Deterrent Systems...................................2-20
Content Theft-Deterrent................................2-20
Passlock
®...................................................2-22
TIGHTEN FUEL CAP......................................3-70
Tilt Wheel........................................................ 3-7
Tire Sidewall Labeling......................................5-74
Tire Size.......................................................5-77
Tire Terminology and Denitions........................5-79
Tires.............................................................5-74
Buying New Tires........................................5-86
Chains.......................................................5-91
Changing a Flat Tire....................................5-93
Dual Tire Operation.....................................5-83
If a Tire Goes Flat.......................................5-92
Ination - Tire Pressure................................5-82
Inspection and Rotation................................5-83
Spare Tire................................................5-113
Uniform Tire Quality Grading.........................5-88
Wheel Alignment and Tire Balance.................5-89
Wheel Replacement.....................................5-89
When It Is Time for New Tires......................5-86
To Use the Engine Coolant Heater....................2-26
Tonneau Cover...............................................2-68
Top Strap......................................................1-42
Top Strap Anchor Location...............................1-43
Torque Lock (Automatic Transmission)...............2-51
Total Weight on Your Vehicle’s Tires..................4-88
Tow/Haul Mode (Automatic Transmission)...........2-30
Tow/Haul Mode Light.......................................3-52
Tow/Haul Mode, Overdrive Disable....................3-52Towing
Power Take-Off (PTO)................................4-100
Recreational Vehicle.....................................4-53
Towing a Trailer..........................................4-70
Your Vehicle...............................................4-52
Traction
Assist System (TAS)...................................... 4-9
Manual Selectable Ride................................4-11
Off Light.....................................................3-45
TRACTION ACTIVE........................................3-70
Trailer
Recommendations.......................................4-69
Trailer Brakes.................................................4-90
Trailer Wiring Harness.....................................4-95
TRANS HOT IDLE ENGINE (Allison
Transmission
®Only).....................................3-71
Transfer Case........................................5-58, 5-60
Transmission
Fluid, Automatic..................................5-27, 5-30
Fluid, Manual..............................................5-33
Temperature Gage.......................................3-46
Up-Shift Light..............................................3-43
TRANSMISSION HOT.....................................3-70
Transmission Operation, Automatic....................2-27
Transmission Operation, Manual........................2-31
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-11
Transportation Options...................................... 7-8
Traveling to Remote Areas...............................4-25
Trip Information Button....................................3-54
16