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Data Link Connector: Description and Operation

PCM Wiring:




Left Underside Of I/P:






PURPOSE
Serial Data is a single wire line that the Powertrain Control Module (PCM) uses to communicate and share information with other systems. All major components (IPC, CCC, PCM, DIC, etc.) in the system are always in continuous communication with each other to provide accurate control over the many sub-systems involved. When one or more of these sub-system circuits exceeds pre-programmed limits a malfunction is indicated by a service engine soon warning lamp, and a backup function may be activated until the malfunction is corrected.


OPERATION
The communications line is a single circuit (CKT 800) which is referred to as the data line or serial data line. The Serial Data line is part of the ALDL connector and is used for hookup of test equipment.