Powertrain Control Module
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The Powertrain Control Module is designed to maintain exhaust emission levels to Federal or California standards while providing excellent driveability and fuel efficiency. Review the components and wiring diagrams in order to determine which systems are controlled by the PCM. The PCM monitors numerous engine and vehicle functions. The PCM controls the following operations:
^ Fuel control
^ Ignition Control (IC)
^ Knock Sensor (KS) system
^ Automatic transmission shift functions
^ Cruise Control Enable
^ Evaporative Emission (EVAP) Purge
^ A/C Clutch Control
^ Cooling Fan Control