Powertrain Control Module
The Powertrain Control Module (PCM) has electronic controls to reduce exhaust emissions while maintaining excellent driveability and fuel economy. PCM is located near air filter box. See Fig 1 . The PCM is the control center of this system. PCM monitors numerous engine and vehicle functions. PCM constantly looks at the information from various sensors and other inputs, and controls the systems that affect vehicle performance and emissions. PCM also performs the diagnostic tests on various parts of the system. PCM can recognize operational problems and alert the driver via the Malfunction Indicator Light (MIL). When PCM detects a malfunction, it stores a Diagnostic Trouble Code (DTC). The problem area is identified by the particular DTC that is set. The control module supplies a buffered voltage to various sensors and switches. Review components and wiring diagrams in order to determine which systems are controlled by the PCM.
The following are some of the functions that the PCM controls:
- Engine fueling.
- Ignition Control (IC).
- Knock Sensor (KS) system.
- EVAP emission system.
- EGR system.
- Automatic transmission functions.
- Generator.
- A/C clutch control.
- Cooling fan control.