Engine Controls - System/Component Tests: Introduction

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

NOTE: Testing individual components does not isolate shorts or open circuits. 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 shorted or open wiring harness.

CHART REFERENCE

System Or Component	Diagnostic Information Location
Malfunction Indicator Light	See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in BASIC DIAGNOSTIC PROCEDURES
DLC & MIL On Steady	See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in BASIC DIAGNOSTIC PROCEDURES
No Scan Tool Data	See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in BASIC DIAGNOSTIC PROCEDURES
No-Start Diagnosis	See ENGINE CRANKS BUT WILL NOT RUN in BASIC DIAGNOSTIC PROCEDURES
Injector Circuit Diagnosis	See FUEL SYSTEM DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES
Fuel Pump Relay	See FUEL PUMP RELAY TESTING in BASIC DIAGNOSTIC PROCEDURES
Fuel System Diagnosis	See FUEL SYSTEM DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES
Fuel Injector Balance	See FUEL SYSTEM
MAP Sensor	See ENGINE SENSORS & SWITCHES
IAC Motor	See IDLE CONTROL SYSTEM under FUEL SYSTEM
Fuel Injector Balance Test	See FUEL SYSTEM
Fuel Evaporation Control	See EMISSION SYSTEMS & SUB-SYSTEMS
Ignition Control Circuit	See IGNITION SYSTEM
ESC Ignition Check	See IGNITION SYSTEM
EGR System	See EMISSION SYSTEMS & SUB-SYSTEMS
Tachometer Control Circuit	See MISCELLANEOUS PCM CONTROLS
Torque Converter Clutch	See MISCELLANEOUS PCM CONTROLS
Manual Transmission Shift Lights	See MISCELLANEOUS PCM CONTROLS
A/C Clutch Control	See MISCELLANEOUS PCM CONTROLS
A/C Clutch Control Circuit	See AIR CONDITIONING & HEATING SERVICE & REPAIR