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Engine Control Module: Description and Operation

POWERTRAIN CONTROL MODULE
The center of the electronic engine control (EEC) system is a microprocessor called the PCM. The PCM receives input from sensors and other electronic components. Based on information received and programmed into its memory, the PCM generates output signals to control various relays, solenoids, and actuators. The hybrid vehicle uses a 150-pin PCM which has 3 separate electrical harness connectors.

The PCM is located behind the instrument panel (cowl), center to both driver and passenger sides (access from the engine compartment).