Chevrolet Silverado 1500 2003 – 2003 GENERAL MOTORS Sierra Silverado

Chevrolet Silverado 1500 2003 - BUZZERS, RELAYS & TIMERS

Chevrolet Silverado 1500 2003 BUZZERS, RELAYS & TIMERS LOCATION

Component	Location
A/C COMP Relay	In underhood fuse block.
Auxiliary Battery Relay	At right rear of engine compartment. See Fig. 9.
DEFOG RELAY	In I/P relay block.
DRL Relay	In underhood fuse block.
DRIVER UNLOCK Relay	In left I/P fuse block.
Engine Glow Plug Relay (6.6L VIN 1)	At left rear of engine. See Fig. 11.
FOG LP Fuse	In underhood fuse block.
F/PMP Relay	In underhood fuse block.
Fuel Pump Relay (Secondary)	On underhood fuse block bracket.
HDLP-HI Relay	In underhood fuse block.
HDLP-LOW Relay	In underhood fuse block.
HORN Relay	In underhood fuse block.
IGN 1 Relay	In underhood fuse block.
LOCK Relay	In left I/P fuse block.
PARK LP Relay	In underhood fuse block.
Power Take-Off Relay	On underhood fuse block bracket.
Roof Beacon Relay	At lower left "B" pillar.
STARTER Relay	In underhood fuse block.
UNLOCK Relay	In left I/P fuse block.
W/S WASH Relay	In underhood fuse block.

Chevrolet Silverado 1500 2003 - CIRCUIT PROTECTION DEVICES

Chevrolet Silverado 1500 2003 CIRCUIT PROTECTION DEVICES LOCATION

Component	Location
I/P Relay Block	Below left side of dash, left of steering column.
Left I/P Fuse Block	On lower left side of dash.
Right I/P Fuse Block	On lower right side of dash.
Underhood Fuse Block	At left side of engine compartment, near battery.

Chevrolet Silverado 1500 2003 - CONTROL UNITS

Chevrolet Silverado 1500 2003 CONTROL UNITS LOCATION

Component	Location
Blower Motor Control Processor	Behind right side of dash, on HVAC assembly.
Body Control Module	On lower left side of dash, below steering column.
Cruise Control Module	In left rear of engine compartment, on firewall.
Driver Door Module	Behind driver's door trim panel, below switch assembly.
Electronic Brake Control Module	On left side of inner frame.
Engine Control Module (6.6L VIN 1)	At left front of engine compartment.
Front Passenger Door Module	Behind front passenger's door trim panel, below switch assembly.
Fuel Injector Control Module (6.6L VIN 1)	Under engine air intake duct.
HVAC Control Module	Behind center of dash.
Ignition Control Module (4.3L VIN W)	At right rear of engine, near ground strap.
Inflatable Restraint I/P Module	Behind right side of dash.
Inflatable Restraint Sensing/Diagnostic Module	Under left front seat.
Memory Seat Module	Underside of left front seat.
Powertrain Control Module (PCM)	On left front of engine compartment. See Fig. 10.
Rear Wheel Steering Control Module	At left rear of vehicle, near spare tire bracket.
Throttle Actuator Control Module (Except 4.3L)	At left rear of engine compartment.
Transfer Case Shift Control Module	Behind headlamp switch.
Transmission Control Module	At left front of engine compartment.
Vehicle Communication Interface Module	Behind passenger air bag module.
Windshield Wiper Motor Module	Under windshield cowl, between wiper arms.

Chevrolet Silverado 1500 2003 - MOTORS

Chevrolet Silverado 1500 2003 MOTORS LOCATION

Component	Location
Air Temperature Actuator (Left)	At bottom center of HVAC control assembly.
Air Temperature Actuator (Right)	At top center of HVAC control assembly.
Front Axle Actuator	On right side of center, on axle housing.
Fuel Pump (6.6L VIN 1)	In left side frame rail.
Fuel Pump & Sender Assembly (Primary) (Gas engines)	In primary fuel tank.
Fuel Pump & Sender Assembly (Secondary) (Gas engines)	In secondary fuel tank.
Fuel Transfer Pump (6.6L VIN 1)	In rear fuel tank.
Mode Actuator	On left side of HVAC module.
Recirculation Actuator	On top center of HVAC module.
Supplemental Brake Assist Pump Motor	Mounted to power brake booster.
Windshield Washer Fluid Pump	In washer fluid reservoir.

Chevrolet Silverado 1500 2003 - SENDING UNITS & SENSORS

Chevrolet Silverado 1500 2003 SENDING UNITS & SENSORS LOCATION

Component	Location
A/C Refrigerant Pressure Sensor	In air conditioning muffler hose assembly.
Accelerator Pedal Position Sensor (Except 4.3L)	Driver's floor board, behind accelerator pedal.
Air Temperature Sensor Assembly (Inside)	In headliner, above driver.
Air Temperature Sensor (Lower Left)	In lower left floor duct assembly.
Air Temperature Sensor (Lower Right)	At bottom center of HVAC box, in floor duct.
Air Temperature Sensor (Outside)	At center of core support, behind grille.
Air Temperature Sensor (Upper)	Below dash trim panel, in upper duct.
Ambient Air Temperature Sensor	In right front bumper filler assembly.
Ambient Light Sensor	On top center of dash.
Automatic Transmission Fluid Temperature Sensor	In automatic transmission.
Automatic Transmission Input Shaft Speed Sensor	In automatic transmission.
Automatic Transmission Turbine Speed Sensor	In upper left of transmission.
Barometric Pressure Sensor (6.6L VIN 1)	On left side of engine.
Boost Sensor (6.6L VIN 1)	On right side of engine, on intake manifold.
Camshaft Position Sensor (4.3L VIN W)	In distributor.
Camshaft Position Sensor (4.8L VIN V)	On top center rear of engine.
Camshaft Position Sensor (5.3L VIN T)	On top center rear of engine.
Camshaft Position Sensor (6.0L VIN U)	On top center rear of engine.
Camshaft Position Sensor (6.6L VIN 1)	On front of engine, near cooling fan pulley.
Camshaft Position Sensor (8.1L VIN G)	On left side of timing cover.
Crankshaft Position (CKP) Sensor (4.3L VIN W)	On bottom front of engine, near crank pulley. See Fig. 2.
Crankshaft Position (CKP) Sensor (4.8L VIN V)	On lower right rear of engine block. See Fig. 7.
Crankshaft Position (CKP) Sensor (5.3L VIN T)	On lower right rear of engine block. See Fig. 7.
Crankshaft Position (CKP) Sensor (6.0L VIN U)	On lower right rear of engine block. See Fig. 7.
Crankshaft Position (CKP) Sensor (6.6L VIN 1)	On right side of engine front cover.
Crankshaft Position (CKP) Sensor (8.1L VIN G)	On top left rear of engine block, near bellhousing. See Fig. 8.
Engine Coolant Temperature (ECT) Sensor (4.3L VIN W)	On rear side of left cylinder head. See Fig. 3.
Engine Coolant Temperature (ECT) Sensor (4.8L VIN V)	On front side of left cylinder head. See Fig. 5.
Engine Coolant Temperature (ECT) Sensor (5.3L VIN T)	On front side of left cylinder head. See Fig. 5.
Engine Coolant Temperature (ECT) Sensor (6.0L VIN U)	On front side of left cylinder head. See Fig. 5.
Engine Coolant Temperature (ECT) Sensor (6.6L VIN 1)	On top front of engine. See Fig. 11.
Engine Coolant Temperature Sensor (8.1L VIN G)	At middle of right cylinder head.
Engine Oil Pressure (EOP) Sensor (4.8L VIN V)	On top rear of engine.
Engine Oil Pressure (EOP) Sensor (5.3L VIN T)	On top rear of engine.
Engine Oil Pressure (EOP) Sensor (6.0L VIN U)	On top rear of engine.
Engine Oil Pressure (EOP) Sensor (8.1L VIN G)	On top rear of engine. See Fig. 8.
Fuel Composition Sensor	At left side of engine compartment, attached to fuel lines.
Fuel Level Sensor (Primary)	In primary fuel tank.
Fuel Level Sensor (Secondary)	In secondary fuel tank.
Fuel Pump & Sender Assembly (Primary)	In primary fuel tank.
Fuel Pump & Sender Assembly (Secondary)	In secondary fuel tank.
Fuel Rail Pressure Sensor (6.6L VIN 1)	Under intake manifold shield, on fuel rail.
Fuel Tank Pressure Sensor	On fuel tank, integral to fuel pump & sender assembly.
Heated Oxygen Sensor Bank No. 1 Sensor No. 1	In left exhaust pipe, before catalytic converter.
Heated Oxygen Sensor Bank No. 1 Sensor No. 2	In left exhaust pipe, after catalytic converter.
Heated Oxygen Sensor Bank No. 2 Sensor No. 1	In right exhaust pipe, before catalytic converter.
Heated Oxygen Sensor Bank No. 2 Sensor No. 2	In right exhaust pipe, after catalytic converter.
Inflatable Restraint Front End Discriminating Sensor (Left)	On left front of vehicle, by core support.
Inflatable Restraint Front End Discriminating Sensor (Right)	On right front of vehicle, by core support.
Intake Air Temperature (IAT)/Mass Airflow (MAF) Sensor	In air induction tube. See Fig. 9.
Knock Sensor (KS) (4.3L VIN W)	On rear of engine block. See Fig. 1.
Knock Sensors (KS) (4.8L VIN V)	In valley, under intake manifold. See Fig. 6.
Knock Sensors (KS) (5.3L VIN T)	In valley, under intake manifold. See Fig. 6.
Knock Sensors (KS) (6.0L VIN U)	In valley, under intake manifold. See Fig. 6.
Knock Sensor Bank No. 1 (8.1L VIN G)	On left side of engine, forward of oil filter.
Knock Sensor Bank No. 2 (8.1L VIN G)	On right side of engine, forward of starter.
Manifold Absolute Pressure (MAP) Sensor (4.3L VIN W)	On top rear of engine, on intake manifold. See Fig. 4.
Manifold Absolute Pressure (MAP) Sensor (4.8L VIN V)	On top rear of engine, on intake manifold. See Fig. 5.
Manifold Absolute Pressure (MAP) Sensor (5.3L VIN T)	On top rear of engine, on intake manifold. See Fig. 5.
Manifold Absolute Pressure (MAP) Sensor (6.0L VIN U)	On top rear of engine, on intake manifold. See Fig. 5.
Manifold Absolute Pressure (MAP) Sensor (8.1L VIN G)	On top rear of engine, on intake manifold.
Propshaft Speed Sensor (Front)	On left front side of transfer case.
Propshaft Speed Sensor (Rear)	On transfer case extension housing.
Throttle Position (TP) Sensor (4.3L VIN W)	On throttle body assembly. See Fig. 1.
Vehicle Speed Sensor (2WD)	On left rear side of transmission.
Vehicle Speed Sensor (4WD)	On left side of transfer case.
Washer Fluid Level Sensor	In washer fluid reservoir.
Water In Fuel Sensor (6.6L VIN 1)	On fuel filter element.
Wheel Speed Sensor (Left Front)	On left front wheel hub assembly.
Wheel Speed Sensor (Right Front)	On right front wheel hub assembly.

Chevrolet Silverado 1500 2003 - SOLENOIDS & SOLENOID VALVES

Chevrolet Silverado 1500 2003 SOLENOIDS & SOLENOID VALVES LOCATION

Component	Location
Evaporative Emissions (EVAP) Canister Purge Solenoid (4.3L VIN W)	At right side of engine, attached to intake manifold. See Fig. 1.
Evaporative Emissions (EVAP) Canister Purge Solenoid (4.8L VIN V)	Behind throttle body, near front of engine. See Fig. 5.
Evaporative Emissions (EVAP) Canister Purge Solenoid (5.3L VIN T)	Behind throttle body, near front of engine. See Fig. 5.
Evaporative Emissions (EVAP) Canister Purge Solenoid (6.0L VIN U)	Behind throttle body, near front of engine. See Fig. 5.
Evaporative Emissions (EVAP) Canister Purge Solenoid (8.1L VIN G)	Left side of throttle body, near left of engine.
Evaporative Emissions Canister Vent Solenoid	On left frame rail at fuel tank. See Fig. 12.
Exhaust Gas Recirculation (EGR) Valve (8.1L VIN G)	On top rear center of engine. See Fig. 8.
Idle Air Control Valve (4.3L VIN W)	Mounted to throttle body. See Fig. 1.
Pressure Control Solenoid Valve	In automatic transmission.
Shock Absorber Solenoid (Left Front)	Part of left front shock.
Shock Absorber Solenoid (Left Rear)	Part of left rear shock.
Shock Absorber Solenoid (Right Front)	Part of right front shock.
Shock Absorber Solenoid (Right Rear)	Part of right rear shock.
Torque Converter Clutch Pulse Width Modulation Solenoid Valve	In automatic transmission.
Torque Converter Clutch Solenoid Valve	In automatic transmission.
Trim Solenoid A	In automatic transmission.
Trim Solenoid B	In automatic transmission.

Chevrolet Silverado 1500 2003 - SWITCHES

Chevrolet Silverado 1500 2003 SWITCHES LOCATION

Component	Location
A/C High Pressure Switch (6.6L VIN 1)	On right side of compressor. See Fig. 11.
A/C Low Pressure Switch	On right side of accumulator. See Fig. 9.
Automatic Transmission Fluid Pressure Manual Valve Position Switch	In automatic transmission.
Back-Up Lamp Switch	On left side of transmission.
Brake Fluid Level Switch	On left side of brake fluid reservoir.
Brake Pressure Differential Switch	In brake line under master cylinder.
Clutch Start Switch	On top of clutch pedal assembly.
Coolant Level Switch	In coolant reservoir.
Engine Oil Level Switch (Except 6.6L)	On right side of oil pan.
Engine Oil Level Switch (6.6L VIN 1)	On left rear of oil pan.
Engine Oil Pressure (EOP) Switch (4.3L VIN W)	On top rear of engine. See Fig. 1.
Park Brake Switch	Part of park brake assembly.
Park/Neutral Position Switch	On left side of transmission.
Pressure Switch Manifold	In automatic transmission.
Stoplamp Switch	On top of brake pedal bracket.
Surge Tank Switch (6.6L VIN 1)	On surge tank.

Chevrolet Silverado 1500 2003 - MISCELLANEOUS

Chevrolet Silverado 1500 2003 MISCELLANEOUS LOCATION

Component	Location
Audio Amplifier	Under rear of center console.
Back-Up Alarm	At rear bumper.
Cellular & Navigation Antenna	Mounted to roof, near left "A" pillar.
Data Link Connector	Under left side of dash, below steering column.
Fuel Heater (6.6L VIN 1)	On top of fuel filter element.
Ignition Coil (4.3L VIN W)	On top right side of engine. See Fig. 1.
Ignition Coil (4.8L VIN V)	On top of left & right valve covers.
Ignition Coils (5.3L VIN T)	On top of left & right valve covers.
Ignition Coils (6.0L VIN U)	On top of left & right valve covers.
Ignition Coils (8.1L VIN G)	On top of left & right valve covers.
Intake Air Heater (6.6L VIN 1)	Under intake manifold sight shield, inside air intake pipe.

Chevrolet Silverado 1500 2003 - CONNECTORS

Chevrolet Silverado 1500 2003 CONNECTORS LOCATION

Component	Location
C100 (Black, 16 Pin)	Under underhood fuse block.
C102 (Black, 8 Pin)	Under underhood fuse block.
C104 (Black, 12 Pin)	Front side of fuse block.
C105 (Black, 10 Pin)	Near underhood fuse block.
C107 (6.6L VIN 1) (Black, 38 Pin)	On top of left valve cover. See Fig. 11.
C108 (6.6L VIN 1) (Black, 24 Pin)	On top of left valve cover. See Fig. 11.
C109 (Black, 4 Pin)	On top of valve cover.
C110 (Black, 4 Pin)	On top of valve cover.
C111 (Black, 4 Pin)	On top of valve cover.
C112 (Black, 4 Pin)	At left rear of engine compartment.
C115 (Black, 24 Pin)	At left rear of engine compartment.
C116 (Black, 1 Pin)	Attached to underhood fuse block.
C125 (Light Gray, 8 Pin)	On radiator support.
C127 (Light Gray, 7 Pin)	On radiator support.
C148 (Light Gray, 7 Pin)	On top left side of engine.
C149 (Light Gray, 7 Pin)	On top right side of engine.
C150 (Black, 4 Pin)	On left inner fender.
C151 (Black, 12 Pin)	On left inner fender.
C152 (Blue, 12 Pin)	Under underhood fuse block.
C153 (Black, 3 Pin)	On left inner fender.
C154 (Black, 3 Pin)	On left inner fender.
C155 (Black, 10 Pin)	Near left top front of engine.
C198 (Black, 1 Pin)	On left inner fender.
C201 (Black, 32 Pin)	On steering column.
C202 (Black, 12 Pin)	Behind left side of dash.
C206 (Light Gray, 22 Pin)	Behind left kick panel.
C210 (Black, 2 Pin)	Behind left side of dash.
C214	Behind upper left side of dash.
C220 (Gray, 24 Pin)	Behind center of dash.
C221 (Yellow, 4 Pin)	Behind left kick panel.
C222 (Yellow, 4 Pin)	Behind right kick panel.
C223 (Black, 16 Pin)	Behind left kick panel.
C230 (Black, 2 Pin)	Behind upper right side of dash.
C249 (Black, 4 Pin)	Behind center of dash.
C250 (Gray, 6 Pin)	Behind left side of dash.
C305 (Black, 16 Pin)	Under left front seat.
C306 (Black, 40 Pin)	Under front floor console.
C310 (Natural, 17 Pin)	At left "B" pillar.
C320 (Light Gray, 13 Pin)	Under left front seat.
C321 (24 Pin)	Under left front seat.
C322 (Natural, 10 Pin)	Under left front seat.
C323 (Black, 6 Pin)	Under left front seat.
C324 (Black, 8 Pin)	Under left front seat.
C325 (Gray, 6 Pin)	Under left front seat.
C326 (Gray, 6 Pin)	Under right front seat.
C329 (Gray, 4 Pin)	Under right front seat.
C350 (Black, 2 Pin)	At top of transfer case.
C388 (Black, 6 Pin)	Under right front seat.
C396 (Black, 17 Pin)	At right "B" pillar.
C399 (Black, 16 Pin)	Under right front seat.
C404 (Black, 2 Pin)	Under rear bumper.
C405 (Black, 2 Pin)	Under rear bumper.

Chevrolet Silverado 1500 2003 - GROUNDS

Chevrolet Silverado 1500 2003 GROUNDS LOCATION

Component	Location
G100	On lower left of radiator core support.
G102 (4.3L VIN W)	On lower right front of engine block.
G102 (4.8L VIN V)	On left side of engine block. See Fig. 5.
G102 (5.3L VIN T)	On left side of engine block. See Fig. 5.
G102 (6.0L VIN U)	On left side of engine block. See Fig. 5.
G102 (8.1L VIN G)	On left side of engine block.
G103 (4.3L VIN W)	On right rear of engine block. See Fig. 1.
G103 (4.8L VIN V)	On right rear of engine block.
G103 (5.3L VIN T)	On right rear of engine block.
G103 (6.0L VIN U)	On right rear of engine block.
G103 (8.1L VIN G)	On right rear of engine block.
G104 (4.3L VIN W)	On left rear of engine block. See Fig. 1.
G104 (4.8L VIN V)	On left rear of engine block.
G104 (5.3L VIN T)	On left rear of engine block.
G104 (6.0L VIN U)	On left rear of engine block.
G104 (8.1L VIN G)	On left rear of engine block.
G105	On lower right front of engine block.
G106	On right front of engine block.
G110	On left front body mount.
G200	Behind right side of dash, near right "A" pillar.
G203	Behind left side of dash, near left "A" pillar.
G302	On left rear body mount.
G304	Under left front seat.
G305	On left "B" pillar.
G306	On right "B" pillar.
G390	Near "C" pillar.
G401	On spare tire hoist bracket.
G403	On left rear frame body mount bracket.
G410	On right rear inner side body panel.

Chevrolet Silverado 1500 2003 - SPLICES

Chevrolet Silverado 1500 2003 SPLICES LOCATION

Component	Location
SP205	In I/P harness.
SP207	In I/P harness.
SP250	In infotainment jumper harness.
S100	In forward lamp harness.
S101	In engine harness.
S102	In engine harness.
S103	In engine harness.
S104	In engine harness.
S107	In forward lamp harness.
S110	In engine harness.
S111	In chassis harness.
S119	In engine harness.
S150	In chassis harness.
S151	In ignition coil jumper harness.
S152	In injector jumper harness.
S153	In ignition coil jumper harness.
S154	In injector jumper harness.
S156	In engine harness.
S157	In engine harness.
S159	In engine harness.
S160	In ignition coil jumper harness.
S161	In I/P harness.
S162	In I/P harness.
S163	In engine harness.
S165	In engine harness.
S197	In battery positive cable.
S200	At roof marker lights.
S201	At roof marker lights.
S202	In I/P harness.
S205	In I/P harness.
S206	In I/P harness.
S207	In headliner harness.
S212	In I/P harness.
S213	In I/P harness.
S214	In I/P harness.
S215	In brake clutch harness.
S216	In steering column harness.
S217	In steering column harness.
S218	In I/P harness.
S219	In brake clutch harness.
S240	In steering column harness.
S241	In steering column harness.
S301	In console harness.
S307	In console harness.
S309	In driver seat harness.
S310	In driver seat harness.
S311	In driver seat harness.
S314	In driver seat harness.
S315	In driver seat harness.
S316	In driver seat harness.
S322	In driver seat harness.
S328	In passenger seat harness.
S329	In passenger seat harness.
S333	In console harness.
S350	In chassis harness.
S408	In left rear lamp harness.
S412	In left rear lamp harness.
S413	In right rear lamp harness.
S480	In right rear lamp harness.
S710	In left rear door harness.
S810	In right rear door harness.