GM Service Manual Online
For 1990-2009 cars only

Name

Location

Locator View

Connector End View

A/C Compressor Clutch

On the upper left front of the engine, on the front of the A/C compressor behind the pulley that is part of the A/C compressor

HVAC Component Views in HVAC

HVAC Connector End Views in HVAC

A/C Compressor High Pressure Cutoff Switch

On the rear plate of the A/C compressor housing

HVAC Component Views in HVAC

HVAC Connector End Views in HVAC

A/C Compressor Refrigerant Pressure Switch

Body Builder Installed

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HVAC Connector End Views in HVAC

A/C Compressor Relay

In the engine wiring harness junction block (underhood fuse relay center), the center relay in the column at the left side

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Accelerator Pedal Position (APP) Sensor

On the accelerator pedal mount

Engine Controls Component Views

Engine Controls Connector End Views

Camshaft Position (CMP) Sensor

Between the cylinder banks, just ahead of the bell housing

Engine Controls Component Views

Engine Controls Connector End Views

Crankshaft Position (CKP) Sensor

On the crankshaft behind the drive belt pulley

Engine Controls Component Views

Engine Controls Connector End Views

Cruise Control Switch

On the left side of the steering column, part of the turn signal stalk

Cruise Control Component Views in Cruise Control

Cruise Control Connector End Views in Cruise Control

Data Link Connector (DLC)

On the cowl, under the steering column near the floor

Data Link Communications Component Views in Data Link Communications

Data Link Communications Connector End Views in Data Link Communications

Electronic Brake Control Module (EBCM)

On the front cross member, near the RH frame rail

Antilock Brake System Component Views in Antilock Brakes

Antilock Brake System Connector End Views in Antilock Brakes

Engine Coolant Level Switch

On the lower right side of the radiator surge tank

Engine Controls Component Views

Engine Controls Connector End Views

Engine Coolant Temperature (ECT) Sensor

On the right side of the engine, center, above the spark plugs

Engine Controls Component Views

Engine Controls Connector End Views

Engine Wiring Harness Junction Block (Underhood Fuse Relay Center)

At the lower LH corner of the cowl

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Evaporative Emissions (EVAP) Canister Purge Valve

On the left side of the intake manifold, forward of the center

Engine Controls Component Views

Engine Controls Connector End Views

Exhaust Gas Recirculation (EGR) Valve

On the left side of the intake manifold, near the center

Engine Controls Component Views

Engine Controls Connector End Views

Fuel Injectors

Under the intake manifold, between the cylinder banks

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Engine Controls Connector End Views

Fuel Pump Module

On top of the fuel tank

Engine Controls Component Views

Engine Controls Connector End Views

Fuel Pump (FP) Relay

In the engine wiring harness junction block (underhood fuse relay center), top relay in the column at the left side

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Fuse Block

Body builder installed

Electrical Center Identification Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Heated Oxygen Sensors (HO2S) Bank 1,2 Sensor 1

In the exhaust pipes, along side the bell housing

Engine Controls Component Views

Engine Controls Connector End Views

Heated Oxygen Sensors (HO2S) Bank 1,2 Sensor 2

In the exhaust pipes just to the rear of the catalytic converters

Engine Controls Component Views

Engine Controls Connector End Views

Ignition Coils

Above each spark plug, mounted on top of the rocker covers

Engine Controls Component Views

Engine Controls Connector End Views

Instrument Cluster

Body builder installed

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Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gauges and Console

Intake Air Temperature (IAT) Sensor

In the intake duct, just behind the air cleaner

Engine Controls Component Views

Engine Controls Connector End Views

Knock Sensors (KS)

On both sides, near the center of the engine block below the exhaust manifold

Engine Controls Component Views

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Manifold Absolute Pressure (MAP) Sensor

On the front top side of the engine behind the thermostat housing

Engine Controls Component Views

Engine Controls Connector End Views

Mass Air Flow (MAF) Sensor

In the plastic intake duct just ahead of the aluminum duct

Engine Controls Component Views

Engine Controls Connector End Views

Park/Neutral Position (PNP) Switch

In the left side of the transmission housing, toward the bell housing

Engine Controls Component Views

Engine Controls Connector End Views

Powertrain Control Module (PCM)

Above the radiator to the right of the driver island

Engine Controls Component Views

Powertrain Control Module Connector End Views

Speedometer Adapter Module

On the left side of the steering column support

Engine Controls Component Views

Engine Controls Connector End Views

Starter Relay

In the engine wiring harness junction block (underhood fuse relay center), outside row at the bottom

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Stoplamp Switch

On the brake pedal linkage

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Throttle Actuator Control (TAC) Module

Under the steering column support

Engine Controls Component Views

Engine Controls Connector End Views

Throttle Actuator Motor

On top of the engine, on the right side of the throttle body

Engine Controls Component Views

Engine Controls Connector End Views

Throttle Position (TP) Sensor

On manifold near the air intake

Engine Controls Component Views

Engine Controls Connector End Views

Vehicle Speed Sensor

On the transmission tailshaft housing, left side

Engine Controls Component Views

Engine Controls Connector End Views

C100

At the lower left corner of the bulkhead; the IP harness end is attached to the bulkhead

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C101

On the engine side of the bulkhead, near C100

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C102

On top of the valve cover, at the front of the LH cylinder bank

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C103

On top of the valve cover, at the rear of the RH cylinder bank

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C105

At the rear of the left cylinder head

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C110

On top of the transmission

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C202

On top of the steering column support

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C203

On top of the steering column support

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

G102

On the front center of the engine thermostat housing

Power and Grounding Component Views in Wiring Systems

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G103

On the rear of the RH cylinder bank

Power and Grounding Component Views in Wiring Systems

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G104

On the rear of the RH cylinder bank

Power and Grounding Component Views in Wiring Systems

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G200

On the top of the steering column support

Power and Grounding Component Views in Wiring Systems

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G400

Rear chassis components ground, on the right frame rail near the park brake pump

Power and Grounding Component Views in Wiring Systems

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P100

Main wiring pass-through on the bulkhead

Harness Routing Views in Wiring Systems

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S100

In the engine harness, about 14 cm (6 in) from the fuel injector breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S101

In the engine harness, about 20 cm (8 in) from the generator breakout toward the fuel injector breakout

Harness Routing Views in Wiring Systems

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S102

In the engine harness, about 27 cm (11 in) from the fuel injector breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S103

In the engine harness, about 21 cm (8 in) from the fuel injector breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S106

In the engine harness, about 26 cm (10 in) from the PCM breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S107

In the engine harness, about 20 cm (8 in) from the PCM breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S108 (A/C Diode Splice)

In the engine harness, about 10 cm (4 in) from the A/C compressor breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S109 (A/C Diode Splice)

In the engine harness, about 10 cm (4 in) from the A/C compressor breakout toward the generator breakout

Harness Routing Views in Wiring Systems

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S110

In the breakout for the PCM connectors, about 10 cm (4 in) from the main engine harness

Harness Routing Views in Wiring Systems

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S113

In the main engine harness, about 7 cm (3 in) from the breakout for the LH wheel speed sensor toward the breakout for the ABS system

Harness Routing Views in Wiring Systems

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S114

In the main engine harness, about 7 cm (3 in) from the breakout for the ABS system toward the breakout for the LH wheel speed sensor

Harness Routing Views in Wiring Systems

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S118

In the engine harness branch leading to the ABS system, about 13 cm (5 in) from the main engine harness

Harness Routing Views in Wiring Systems

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S160

In Bank 1 fuel injection harness

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S161

In Bank 2 fuel injection harness

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S162

In Bank 2 ignition coil harness

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S163

In Bank 1 ignition coil harness

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S164

In Bank 1 ignition coil harness

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S165

In Bank 2 ignition coil harness

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S166

In Bank 1 ignition coil harness

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S167

In Bank 2 ignition coil harness

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S201

In the IP harness, about 11 cm (4 in) toward the IP wiring harness junction block from the breakout for the transmission range control

Harness Routing Views in Wiring Systems

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S202

In the IP harness, about 16 cm (6 in) toward the IP wiring harness junction block from the breakout for the transmission range control

Harness Routing Views in Wiring Systems

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S207

In the IP harness, about 3 cm (1 in) toward the stoplamp switch breakout from the breakout for the transmission range control

Harness Routing Views in Wiring Systems

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S221

In the IP harness, about 9 cm (3 in) toward the speedometer adapter module from the breakout for the transmission range control

Harness Routing Views in Wiring Systems

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S222

In the IP harness, about 5 cm (2 in) toward the fuse block from the stoplamp switch breakout

Harness Routing Views in Wiring Systems

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S223

In the IP harness stoplamp switch breakout, about 30 cm (12 in) from the main harness

Harness Routing Views in Wiring Systems

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S224

In the IP harness stoplamp switch breakout, about 24 cm (9 in) from the main harness

Harness Routing Views in Wiring Systems

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S234

In the IP extension harness, 19 cm (7 in) from the instrument cluster connector

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S235

In the IP extension harness, about 12 cm (5 in) from the instrument cluster connector

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S300

In the rear chassis harness, 96 cm (38 in) toward the engine from the breakout for the park brake actuator position switch

Harness Routing Views in Wiring Systems

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S301

In the rear chassis harness, about 56 cm (22 in) toward the engine from the breakout for the park brake actuator position switch

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S401

In the rear chassis harness, about 100 cm (39 in) forward of the fuel pump breakout

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