8D–78
WIRING SYSTEM
Powertrain Control Module (PCM)
General Description
The Powertrain Control Module (PCM) is located in
the passenger compartment.
The PCM constantly monitors the information from
various sensors, and controls the systems that affect
vehicle performance.
The PCM performs the diagnostic function of the
system. It can recognize operational problems, alert
the driver through the Malfunction Indicator Light
(MIL) and store a Diagnostic Trouble Code (DTC) or
DTC(s) which identify the problem areas to aid the
technician in making repairs.
The PCM is designed to process the various input
informations and then sends the necessary
electrical responses to control fuel delivery, spark
timing and other emission control systems. The
input information has an interrelation to more than
one output, therefore, if the one input failed, it could
affect more than one system operation.
Refer to Driveability and Emission in Engine section
and Automatic Transmission in Transmission
section.