Powertrain Control Module

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The powertrain has electronic controls to reduce exhaust emissions while maintaining excellent driveability and fuel economy. The Powertrain Control Module (PCM) is the control center of this system. PCM is located on left front of engine compartment. See Fig 1 . PCM monitors numerous engine and vehicle functions and 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. The PCM can recognize operational problems and alert the driver via the Malfunction Indicator Light (MIL). When PCM detects a malfunction, the PCM stores a 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.

Fig 1: Locating PCM

Courtesy of GENERAL MOTORS CORP.