1997 Ford Escort service engine light

The Powertrain Control Module (PCM) is the central computer which receives data from numerous sensors and switches. The PCM processes information received and then generates output signals to control various relays, solenoids and actuators. The PCM has failure detection and self-diagnostic capability. On A/T, PCM is integrated with the Transaxle Control Module (TCM).
The MIL will illuminate when ignition switch is turned to the ON position (bulb check), or when systems related to the EEC system malfunction during normal engine operation.

If light stay on after engine start and or while driving
PCM detected a malfunction in one of the sensors and need to have system check for codes

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