Computerized Engine Controls: Notes

A Powertrain Control Module (PCM) receives and processes signals from various sensors and switches. See Fig 1. It then generates signals which control ignition timing, fuel injection functions, and various emission control devices. The PCM has system diagnostic capabilities, and will store trouble codes for use by service technicians.

Fig 1: Input Devices & Output Signal ID (Not All Shown)

Courtesy of FORD MOTOR CO.