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Serial Data

PCM Wiring:






PURPOSE
Serial Data is a single wire line that the Powertrain Control Module (PCM) uses to communicate and share information with other systems.


OPERATION
A Serial Data line is part of the ALDL connector and is used for hookup of test equipment.
On vehicles equipped with an automatic transaxle the Powertrain Control Module (PCM) will have an internal serial data line. This line will allow the Engine Controller (EC) to send and receive signals from the Transaxle Controller (TC) and Antilock Brake System (ABS). The EC will control this serial data line within the PCM.

NOTE: The Engine Controller (EC) and Transaxle Controller (TC) are located within the Powertrain Control Module (PCM).