LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2002 >> Astro Van 2WD V6-4.3L VIN X >> Repair and Diagnosis >> Relays and Modules >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Description and Operation >> General Information
April 5, 2026: LEMON Manuals is launched! Read the announcement.

General Information

The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ The fuel control
^ The Ignition Control (IC)
^ The Knock Sensor (KS) system
^ The automatic transmission shift functions
^ The manual transmission
^ The cruise control enable, if so equipped
^ The generator
^ The Evaporative Emissions (EVAP) purge
^ The A/C clutch control, if so equipped
^ The Secondary Air Injection (AIR), if so equipped
^ The Exhaust Gas Recirculation (EGR)

The PCM controls all ignition system functions, and constantly corrects the basic spark timing. The PCM monitors information from various sensor inputs that include the following:
^ The Throttle Position (TP) sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Mass Airflow (MAF) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Vehicle Speed Sensor (VSS)
^ The transmission gear position or range information sensors
^ The engine Knock Sensors (KS)