Engine Controls - System/Component Tests - Gasoline: Introduction

Before testing separate components or systems, perform procedures in BASIC TESTING - GASOLINE article in the ENGINE PERFORMANCE section. Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform procedures in appropriate TESTS W/CODES article in the ENGINE PERFORMANCE section below.

G - TESTS W/CODES - 4.3L
G - TESTS W/CODES - 5.0L
G - TESTS W/CODES - 5.7L
G - TESTS W/CODES - 7.4L

NOTE: Testing individual components does not isolate shorts or opens. Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter and refer to WIRING DIAGRAMS to isolate wiring harness shorts or opens.

The following table provides the location of commonly used diagnostic information. These former "A" and "C" charts are now written in text and inserted into the new Engine Performance workflow. To familiarize yourself with the Engine Performance workflow, see the AA - USING THIS SECTION (GENERAL HELP INFORMATION) article in GENERAL INFORMATION section.

GENERAL MOTORS "A" & "C" CHART REFERENCE

System or Component

Diagnostic Information Location

DIAGNOSTIC CIRCUIT CHECK

⁽¹⁾ See DIAGNOSTIC CKT CHECK

A-1 & A-2, Malfunction Indicator Light (MIL)

⁽¹⁾ See DIAGNOSTIC CKT CHECK

A-3, No-Start

⁽¹⁾ See NO-START DIAGNOSIS

A-5, Fuel Pump Relay

See RELAYS, SOLENOIDS, MOTORS & MODULES

A-6 & A-7, Fuel System Diagnosis

⁽¹⁾ See BASIC FUEL SYSTEM CHECKS

C-1, MAP Sensor

See ENGINE SENSORS & SWITCHES

C-1, Power Steering Pressure Switch

See ENGINE SENSORS & SWITCHES

C-1, Park/Neutral Switch

See ENGINE SENSORS & SWITCHES

C-2, IAC Valve

See IDLE CONTROL SYSTEM

C-3, Canister Purge System

See EMISSION SYSTEMS & SUB-SYSTEMS

C-4, EST Ignition Check

⁽¹⁾ See BASIC IGNITION SYSTEM CHECKS

C-5, ESC Ignition Check

See IGNITION SYSTEM

C-6, Air Injection System

See EMISSION SYSTEMS & SUB-SYSTEMS

C-7, EGR System

See EMISSION SYSTEMS & SUB-SYSTEMS

C-8, Torque Converter Clutch

See MISCELLANEOUS ECM CONTROLS

C-8, Manual Transmission Shift Lights

See MISCELLANEOUS ECM CONTROLS

C-10, A/C Clutch Control

See MISCELLANEOUS ECM CONTROLS

C-12, Electric Cooling Fan Control

⁽²⁾ See MISCELLANEOUS ECM CONTROLS

Injector Balance Test (PFI)

See FUEL CONTROL

⁽¹⁾	See appropriate F - BASIC TESTING - GASOLINE article in the ENGINE PERFORMANCE section.

⁽²⁾	Covered in entirety in appropriate ENGINE COOLING article.