Repair Diagrams for 2003 GMC Sierra 2500 HD Engine, Transmission, Lighting, AC, Electrical & Warning Systems

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Automotix DIY provides automotive consumers and do it yourselfers; the most comprehensive repair information about 2003 GMC Sierra 2500 HD car and truck repair procedures including GMC engine diagrams, wiring diagrams, repair work estimating measures, technical service bulletins, auto body work guidance, starter & alternator replacement procedures, serpentine belt replacement procedures, radiator & hose replacement procedures, tune-up & drivability specifications, quick lube illustrations, preventive maintenance guide, engine light reset instructions, parts removal and install procedures, fuel filter replacement directions, component location diagrams, air filter locations & replacement instructions, a/c system specifications, and general auto service procedures. You don't have to be a car mechanic or technician to know how to fix your 2003 GMC Sierra 2500 HD automobile. Try the Automotix DIY solution today!

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We have info for following modifications of 2003 GMC Sierra 2500 HD

2003 GMC Sierra 2500 HD 6.0 V8 GAS, CID:364, Fuel Injection, Aspiration:364, Engine VIN:, Desg:U
2003 GMC Sierra 2500 HD 8.1 V8 GAS, CID:496, Fuel Injection, Aspiration:496, Engine VIN:, Desg:G
2003 GMC Sierra 2500 HD 6.6 V8 DIESEL, CID:400, Fuel Injection, Aspiration:400, Engine VIN:, Desg:1
2003 GMC Sierra 2500 HD 6.0 V8 CNG, CID:364, Fuel Injection, Aspiration:364, Engine VIN:, Desg:U

WIRING DIAGRAMS FOR 2003 GMC Sierra 2500 HD AUTOMOBILES

OEM drawn wiring diagrams for most 2003 GMC Sierra 2500 HD cars and light trucks sold in the U.S.

2003 GMC Sierra 2500 HD 6.6 V8 DIESEL Wiring Diagram

Components on diagram:

Battery

Starter Relay

Starter

Glow Plug Controller

Generator

2003 GMC Sierra 2500 HD 8.1 V8 GAS Wiring Diagram

Components on diagram:

Tail/Stop Lamp -Right

License Lamp -Right

2003 GMC Sierra 2500 HD 8.1 V8 GAS Wiring Diagram

Components on diagram:

Fuel Injector 5

Fuel Injector 4

Fuel Injector 2

Fuel Injector 3

Fuel Injector 7

2003 GMC Sierra 2500 HD 6.6 V8 DIESEL Wiring Diagram

Components on diagram:

Headlamp Switch

Park Lamp Relay

Body Control Module

2003 GMC Sierra 2500 HD 8.1 V8 GAS Wiring Diagram

Components on diagram:

Body Control Module

Driver Door Module

Front Passenger Door Module

2003 GMC Sierra 2500 HD 8.1 V8 GAS Wiring Diagram

Components on diagram:

1-2 Shift Solenoid Valve

3-2 Shift Solenoid Valve

Torque Converter Clutch Pulse Width Modulation Solenoid Valve

Torque Converter Clutch Solenoid Valve

2-3 Shift Solenoid Valve

2003 GMC Sierra 2500 HD 6.0 V8 GAS Wiring Diagram

Components on diagram:

Rear Defogger Relay

Body Control Module

Rear Defogger Switch

Rear Window Defogger Grid

Heater/Vent/Air Conditioning Control Module

2003 GMC Sierra 2500 HD 8.1 V8 GAS Wiring Diagram

Components on diagram:

Sun Load Sensor

Body Control Module

Ambient Light Sensor

Heater/Vent/Air Conditioning Control Module

Left Solar Sensor

2003 GMC Sierra 2500 HD 6.6 V8 DIESEL Wiring Diagram

Components on diagram:

Engine Control Module

2003 GMC Sierra 2500 HD 6.0 V8 GAS Wiring Diagram

Components on diagram:

Body Control Module

Driver Door Module

Door Key Switch

Door Lock Switch

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Access diagrams and repair information such as wiring diagrams, diagnosis and repair charts, manufacturer service bulletins, and OEM Part numbers of your 2003 GMC Sierra 2500 HD vehicle.