Chevrolet Pickup C3500 1994 - ELECTRICAL COMPONENT LOCATOR 1994 ELEC COMPONENT LOCATION General Motors Corp. - Electrical Component Location

Chevrolet Pickup C3500 1994 - BUZZERS, RELAYS & TIMERS

Chevrolet Pickup C3500 1994 BUZZERS, RELAYS & TIMERS LOCATION

Component	Location
A/C Clutch Relay	On top of A/C-heater housing, behind right side of dash.
Auxiliary Battery Relay	On left front inner fender panel, above wheelwell.
Auxiliary Cooling Fan Relay	On left front inner fender panel, near firewall.
Blower Relays (High/Low)
Front	On top of front A/C-heater blower housing.
Rear	On auxiliary A/C-heater blower housing.
Center High Mounted Stop Light Relay	On right hand side of cowl, in engine compartment.
Cold Advance Relay (6.5L)	On right rear of engine compartment, near battery junction block.
Daytime Running Light (DRL) Relay	Behind left side of dash, below DRL module.
Foglight Relay	Behind left side of dash, above convenience center.
Fuel Pump Relay
4.3L California	On right side of firewall. See Fig. 1.
4.3L W/4L60E A/T	On right side of firewall. See Fig. 2.
4.3L W/4L80E A/T	On right side of firewall. See Fig. 3.
4.3L M/T	On right side of firewall. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On right side of firewall. See Fig. 5.
5.0L & 5.7L M/T	On right side of firewall. See Fig. 6.
5.7L W/4L80E M/T	On right side of firewall. See Fig. 7.
7.4L A/T	On right side of firewall. See Fig. 8.
7.4L M/T	On right side of firewall. See Fig. 9.
Glow Plug Relay (6.5L)	On top left rear of engine. See Fig. 10.
Hazard Flasher Relay	Under left side of dash, near convenience center.
Horn Relay	On convenience center.
Power Amplifier Relay	Under left side of dash, on left of brake pedal bracket.
Power Door Lock Relay	Under left side of dash, on right of brake pedal bracket.
Rear Window Release Relay	Behind left side of dash, above steering column.
Transfer Case Relay	On right side of firewall, near battery junction block cover.
Turn Signal Flasher Relay	On convenience center.

Chevrolet Pickup C3500 1994 - CIRCUIT PROTECTION DEVICES

Chevrolet Pickup C3500 1994 CIRCUIT PROTECTION DEVICES LOCATION

Component	Location
Circuit Breakers	On fuse block.
Battery Junction Block	On right side of firewall.
Convenience Center	Under left side of dash.
Fuel Pump In-Line Fuse
4.3L W/4L80E A/T	On right side of firewall, near fuel pump relay. See Fig. 3.
5.0L & 5.7L W/4L60E A/T	On right side of firewall, near fuel pump relay. See Fig. 5.
5.7L W/4L80E A/T	On right side of firewall, near fuel pump relay. See Fig. 7.
5.0L & 5.7L M/T Heavy Duty	On right side of firewall, near fuel pump relay. See Fig. 6.
Fuse Block
4.3L California	Under left side of dash. See Fig. 1.
4.3L W/4L60E A/T	Under left side of dash. See Fig. 2.
4.3L W/4L80E A/T	Under left side of dash. See Fig. 3.
4.3L M/T	Under left side of dash. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	Under left side of dash. See Fig. 5.
5.0L & 5.7L M/T	Under left side of dash. See Fig. 6.
5.7L W/4L80E A/T	Under left side of dash. See Fig. 7.
6.5L Diesel	Under left side of dash. See Fig. 10.
7.4L A/T	Under left side of dash. See Fig. 8.
7.4L M/T	Under left side of dash. See Fig. 9.
Fusible Links	At battery junction block.
Power Mirror In-Line Fuse	Taped to crossbody harness under right side of dash.

Chevrolet Pickup C3500 1994 - CONTROL UNITS

Chevrolet Pickup C3500 1994 CONTROL UNITS LOCATION

Component	Location
ABS Diode Module	Under left side of dash.
ABS Module	Mounted on side of brake master cylinder.
Audio Alarm Module	On convenience center.
Coolant Level Sensor Module	Behind center of dash.
Cruise Control Module	Under left side of dash. See Fig. 10.
Daytime Running Lights (DRL) Module	Behind left side of dash, taped to panel wiring harness.
Engine Control Module (ECM) (5.0L & 5.7L M/T Heavy Duty)	Behind right side of dash, near blower motor. See Fig. 6.
Glow Plug Controller (6.5L)	On left rear of intake manifold.
Fuel Module
5.7L Heavy Duty	Behind right side of dash, above blower motor. See Fig. 6.
7.4L	Behind left side of dash, behind brake booster.
Ignition Control Module	On center rear of engine, near ignition distributor.
Knock Sensor Module (5.0L/5.7L M/T)	On top right of engine, on valve cover. See Fig. 6.
Powertrain Control Module (PCM)
4.3L California	Behind right side of dash, near blower motor. See Fig. 1.
4.3L W/4L60E A/T	Behind right side of dash, near blower motor. See Fig. 2.
4.3L W/4L80E A/T	Behind right side of dash, near blower motor. See Fig. 3.
4.3L M/T	Behind right side of dash, near blower motor. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	Behind right side of dash, near blower motor. See Fig. 5.
5.7L W/4L80E A/T	Behind right side of dash, near blower motor. See Fig. 7.
6.5L Diesel	Behind right side of dash, near blower motor. See Fig. 10.
7.4L A/T	Behind right side of dash, near blower motor. See Fig. 8.
7.4L M/T	Behind right side of dash, near blower motor. See Fig. 9.
Radio Receiver Module	Behind center of dash.
Transmission Control Module (TCM)	Behind right side of dash.
Wiper Motor Module
Front	On firewall, behind wiper motor.
Rear	On lower inner center of rear window.

Chevrolet Pickup C3500 1994 - SENDING UNITS & SENSORS

Chevrolet Pickup C3500 1994 SENDING UNITS & SENSORS LOCATION

Component	Location
Accelerator Pedal Position Sens	On accelerator pedal bracket. See Fig. 10.
Boost Sensor (6.5L)	On top right center of engine. See Fig. 10.
Coolant Level Sensor	On top right side of radiator.
Coolant Temp. Sending Unit/Switch	On front of left cylinder head.
Crankshaft Position Sensor	On bottom front of engine, near crank pulley. See Fig. 10.
EGR Control Pressure/Baro Sensor	On left side of firewall. See Fig. 10.
Engine Coolant Temp. (ECT) Sensor
4.3L California	On top right front of engine, near thermostat housing. See Fig. 1.
4.3L W/4L60E A/T	On top right front of engine, near thermostat housing. See Fig. 2.
4.3L W/4L80E A/T	On top right front of engine, near thermostat housing. See Fig. 3.
4.3L M/T	On top right front of engine, near thermostat housing. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On top right front of engine, near thermostat housing. See Fig. 5.
5.0L & 5.7L M/T	On top right front of engine, near thermostat housing. See Fig. 6.
5.7L W/4L80E A/T	On top right front of engine, near thermostat housing. See Fig. 7.
7.4L A/T	On top right front of engine, near thermostat housing. See Fig. 8.
7.4L M/T	On top right front of engine, near thermostat housing. See Fig. 9.
Engine Speed Sensor (6.5L)	On top rear of engine.
High Resolution Sensor (6.5L)	On top front of engine. See Fig. 10.
Input Speed Sensor
4.3L W/4L80E A/T	On left front side of transmission. See Fig. 3.
5.7L W/4L80E A/T	On left front side of transmission. See Fig. 7.
7.4L A/T	On left front side of transmission. See Fig. 8.
Intake Air Temp. (IAT) Sensor	On top right center of engine. See Fig. 10.
Knock Sensor
4.3L (2)
California	On left and right rear side of engine, under exhaust manifold. See Fig. 1.
W/4L60E A/T	On left and right rear side of engine, under exhaust manifold. See Fig. 2.
W/4L80E A/T	On left and right rear side of engine, under exhaust manifold. See Fig. 3.
M/T	On left and right rear side of engine, under exhaust manifold. See Fig. 4.
5.0L, 5.7L & 7.4L 5.0L & 5.7L W/4L60E A/T	On lower right front of engine, under exhaust manifold. See Fig. 5.
5.7L W/4L80E A/T	On lower right front of engine, under exhaust manifold. See Fig. 7.
7.4L A/T	On lower right front of engine, under exhaust manifold. See Fig. 8.
7.4L M/T	On lower right front of engine, under exhaust manifold. See Fig. 9.
Low Coolant Sensor	On right rear side of radiator.
Manifold Abs. Press. (MAP) Sensor
Diesel Engines	On left side of firewall, near wiper motor.
Gasoline Engines
4.3L California	On top right of engine, on valve cover. See Fig. 1.
4.3L W/4L60E A/T	On top right of engine, on valve cover. See Fig. 2.
4.3L W/4L80E A/T	On top right of engine, on valve cover. See Fig. 3.
4.3L M/T	On top right of engine, on valve cover. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On top right of engine, on valve cover. See Fig. 5.
5.0L & 5.7L M/T	On top right of engine, on valve cover. See Fig. 6.
7.4L A/T	On top right of engine, on valve cover. See Fig. 8.
7.4L M/T	On top right of engine, on valve cover. See Fig. 9.
Output Speed Sensor (6.5L)	On left rear side of transmission. See Fig. 8.
Throttle Position (TP) Sensor
Diesel Engines	On injection pump throttle valve.
Gasoline Engines
4.3L California	On throttle body assembly. See Fig. 1.
4.3L W/4L60E A/T	On throttle body assembly. See Fig. 2.
4.3L W/4L80E A/T	On throttle body assembly. See Fig. 3.
4.3L M/T	On throttle body assembly. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On throttle body assembly. See Fig. 5.
5.0L & 5.7L M/T	On throttle body assembly. See Fig. 6.
5.7L W/4L80E A/T	On throttle body assembly. See Fig. 7.
7.4L A/T	On throttle body assembly. See Fig. 8.
7.4L M/T	On throttle body assembly. See Fig. 9.
Vehicle Speed Sensor (VSS)
4.3L California	On left side of transmission. See Fig. 1.
4.3L W/4L60E A/T	On left side of transmission. See Fig. 2.
4.3L W/4L80E A/T	On left side of transmission. See Fig. 3.
4.3L M/T	On left side of transmission. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On left side of transmission. See Fig. 5.
5.0L & 5.7L M/T	On left side of transmission. See Fig. 6.
5.7L W/4L80E A/T	On left side of transmission. See Fig. 7.
7.4L A/T	On left side of transmission. See Fig. 8.
7.4L M/T	On left side of transmission. See Fig. 9.
Water-In-Fuel Sensor (6.5L)	In fuel filter assembly, on center rear of engine.
Wheel Speed Sensors	On left and right front wheel hub assembly.

Chevrolet Pickup C3500 1994 - MOTORS

Chevrolet Pickup C3500 1994 MOTORS LOCATION

Component	Location
A/C Inlet/Mode Door Motor	On front and rear (if equipped) A/C-heater housing.
Auxiliary Cooling Fan Motor	In front of radiator.
Blower Motor
Front	Under right side of dash.
Rear	Behind driver's seat, behind trim panel.
Injection Timing Stepper Motor	On top right front of engine. See Fig. 10.
Vacuum Pump (6.5L)	On right front of engine.
Washer Pumps (Front & Rear)	In washer fluid reservoir, near left shock tower.
Wiper Motor (Front)	On left center of firewall.

Chevrolet Pickup C3500 1994 - SOLENOIDS & SOLENOID VALVES

Chevrolet Pickup C3500 1994 SOLENOIDS & SOLENOID VALVES LOCATION

Component	Location
AIR By-Pass Solenoid (4.3L)	On lower right front of engine.
Boost Solenoid (6.5L)	On top center of engine. See Fig. 10.
Canister Purge Solenoid
4.3L California	On top right of engine, near MAP sensor. See Fig. 1.
5.0L & 5.7L W/4L60E A/T	On top left front of engine. See Fig. 5.
7.4L A/T	On top front center of engine. See Fig. 8.
7.4L M/T	On top front center of engine. See Fig. 9.
Cold Start Advance Solenoid (6.5L)	On injection pump, on top right front of engine.
EGR Elec. Vacuum Regulator Solenoid
4.3L W/4L80E A/T	On top of right valve cover. See Fig. 3.
5.0L & 5.7L M/T	On top of right valve cover. See Fig. 6.
5.7L W/4L80E A/T	On top of right valve cover. See Fig. 7.
EGR Pulse Solenoid	On top left rear of engine.
EGR Vacuum Solenoid
4.3L W/4L60E A/T	On top left of engine, on valve cover. See Fig. 2.
4.3L M/T	On top left of engine, on valve cover. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On top left of engine, on valve cover. See Fig. 5.
5.0L & 5.7L M/T	On top left of engine, on valve cover. See Fig. 6.
6.5L Diesel	On top left of engine, on valve cover. See Fig. 10.
EGR Vent Solenoid (6.5L)	On top left rear of engine. See Fig. 10.
Engine Shutoff Solenoid (6.5L)	On left front of engine. See Fig. 10.
Exhaust Pressure Regulator (EPR) Valve (6.5L)	On top left rear of engine.
Fast Idle Solenoid (6.5L)	On injection pump, on right top front of engine.
Front Axle Solenoid	On right rear side of front differential case.
Fuel Shutoff Solenoid (6.5L)	On injection pump, on top front of engine.
Idle Air Control (IAC) Valve
4.3L California	On throttle body assembly. See Fig. 1.
4.3L W/4L60E A/T	On throttle body assembly. See Fig. 2.
4.3L W/4L80E A/T	On throttle body assembly. See Fig. 3.
4.3L M/T	On throttle body assembly. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On throttle body assembly. See Fig. 5.
5.0L & 5.7L M/T	On throttle body assembly. See Fig. 6.
5.7L W/4L80E A/T	On throttle body assembly. See Fig. 7.
7.4L A/T	On throttle body assembly. See Fig. 8.
7.4L M/T	On throttle body assembly. See Fig. 9.
Idle Speed Actuator Solenoid (7.4L)
7.4L A/T	On top right front of engine. See Fig. 8.
7.4L M/T	On top right front of engine. See Fig. 9.
Rear Window Release Solenoid	Behind panel, center of tailgate.

Chevrolet Pickup C3500 1994 - SWITCHES

Chevrolet Pickup C3500 1994 SWITCHES LOCATION

Component	Location
A/C Low Pressure Cycling Switch
4.3L California	On A/C accumulator, on right rear of engine compartment. See Fig. 1.
4.3L W/4L60E A/T	On A/C accumulator, on right rear of engine compartment. See Fig. 2.
4.3L W/4L80E A/T	On A/C accumulator, on right rear of engine compartment. See Fig. 3.
4.3L M/T	On A/C accumulator, on right rear of engine compartment. See Fig. 4.
5.7L W/4L80E A/T	On A/C accumulator, on right rear of engine compartment. See Fig. 7.
7.4L A/T	On A/C accumulator, on right rear of engine compartment. See Fig. 8.
7.4L M/T	On A/C accumulator, on right rear of engine compartment. See Fig. 9.
A/C High Pressure Cut-Out Switch
4.3L California	On A/C compressor. See Fig. 1.
4.3L W/4L60E A/T	On A/C compressor. See Fig. 2.
4.3L W/4L80E A/T	On A/C compressor. See Fig. 3.
4.3L M/T	On A/C compressor. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On A/C compressor. See Fig. 5.
5.0L & 5.7L M/T	On A/C compressor. See Fig. 6.
5.7L W/4L80E A/T	On A/C compressor. See Fig. 7.
7.4L A/T	On A/C compressor. See Fig. 8.
7.4L M/T	On A/C compressor. See Fig. 9.
Auxiliary Cooling Fan Switch	On right cylinder head, near spark plug.
Back-Up Light Switch (M/T)	On left side of transmission.
Brake Pressure Warning Switch	In hydraulic brake combination valve, near master cylinder.
Brake/Cruise/Stoplight Switch	On top of brake pedal bracket.
Clutch/Start Switch	On top of clutch pedal bracket.
Fast Idle Temp. Switch (6.5L)	On right rear of engine, above starter.
Front Axle Solenoid Switch	Near differential case, at front of engine.
Oil Pressure Switch
4.3L California	On top left rear of engine, near distributor. See Fig. 1.
4.3L W/4L60E A/T	On top left rear of engine, near distributor. See Fig. 2.
4.3L W/4L80E A/T	On top left rear of engine, near distributor. See Fig. 3.
4.3L M/T	On top left rear of engine, near distributor. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	On top left rear of engine, near distributor. See Fig. 5.
5.0L & 5.7L M/T	On top left rear of engine, near distributor. See Fig. 6.
5.7L W/4L80E A/T	On top left rear of engine, near distributor. See Fig. 7.
7.4L A/T	On lower left front side of engine. See Fig. 8.
7.4L M/T	On lower left front side of engine. See Fig. 9.
Park/Neutral/Backup Light Switch	On steering column, under dash.
Parking Brake Switch	On parking brake pedal bracket.
Seat Belt Retractor Switch	On driver's seat belt buckle.
Transfer Case Switch	On left front of transfer case.

Chevrolet Pickup C3500 1994 - MISCELLANEOUS

Chevrolet Pickup C3500 1994 MISCELLANEOUS LOCATION

Component	Location
Blower Motor Resistor	On front and rear (if equipped) blower motor housing.
Data Link Connector (DLC)
4.3L California	Under left side of dash, left of steering column. See Fig. 1.
4.3L W/4L60E A/T	Under left side of dash, left of steering column. See Fig. 2.
4.3L W/4L80E A/T	Under left side of dash, left of steering column. See Fig. 3.
4.3L M/T	Under left side of dash, left of steering column. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	Under left side of dash, left of steering column. See Fig. 5.
5.0L & 5.7L M/T	Under left side of dash, left of steering column. See Fig. 6.
5.7L W/4L80E A/T	Under left side of dash, left of steering column. See Fig. 7.
6.5L Diesel	Under left side of dash, left of steering column. See Fig. 10.
7.4L A/T	Under left side of dash, left of steering column. See Fig. 8.
7.4L M/T	Under left side of dash, left of steering column. See Fig. 9.
Fuel Heater (6.5L)	On fuel filter assembly.
Fuel Pump Test Connector
4.3L California	Under left side of dash, DLC terminal "G". See Fig. 1.
4.3L W/4L60E A/T	Under left side of dash, DLC terminal "G". See Fig. 2.
4.3L W/4L80E A/T	Under left side of dash, DLC terminal "G". See Fig. 3.
4.3L M/T	Under left side of dash, DLC terminal "G". See Fig. 4.
5.0L & 5.7L W/4L60E A/T	Under left side of dash, DLC terminal "G". See Fig. 5.
5.0L & 5.7L M/T	Under left side of dash, DLC terminal "G". See Fig. 6.
5.7L W/4L80E A/T	Under left side of dash, DLC terminal "G". See Fig. 7.
7.4L A/T	Under left side of dash, DLC terminal "G". See Fig. 8.
7.4L M/T	Under left side of dash, DLC terminal "G". See Fig. 9.
Fuel Solenoid Driver	On top left center of engine. See Fig. 10.
Idle Speed Actuator (7.4L)
7.4L A/T	On top left center of engine. See Fig. 8.
7.4L M/T	On top left center of engine. See Fig. 9.
Power Amplifier	Under driver's seat.
Vehicle Speed Sensor Buffer
4.3L California	Behind right side of dash. See Fig. 1.
4.3L W/4L60E A/T	Behind right side of dash. See Fig. 2.
4.3L W/4L80E A/T	Behind right side of dash. See Fig. 3.
4.3L M/T	Behind right side of dash. See Fig. 4.
5.0L & 5.7L W/4L60E A/T	Behind right side of dash. See Fig. 5.
5.0L & 5.7L M/T	Behind right side of dash. See Fig. 6.
5.7L W/4L80E A/T	Behind right side of dash. See Fig. 7.
7.4L A/T	Behind right side of dash. See Fig. 8.
7.4L M/T	Behind right side of dash. See Fig. 9.