The PCM is designed to maintain exhaust emission levels to
Federal/California/other 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 following are some of the functions that
the PCM controls: • The engine fueling • The ignition control
(IC) • The knock sensor (KS) system • The evaporative emissions
(EVAP) system • The secondary air injection (AIR) system (if
equipped) • The exhaust gas recirculation (EGR) system • The
automatic transmission functions • The generator • The A/C
clutch control • The cooling fan control Powertrain Control
Module Function. The PCM constantly looks at the information
from various sensors and other inputs and controls systems that
affect vehicle performance and emissions. The PCM also performs
diagnostic tests on various parts of the system. The PCM can
recognize operational problems and alert the dr