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Home >> Cadillac >> 1993 >> Eldorado V8-300 4.9L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Description and Operation
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Information Bus: Description and Operation

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 Data Link Connector ([1][2]DLC) connector and is used for hookup of test equipment.

The use of the communication line allows for the separate controlers to share information. Examples of this may be gage information sent from the PCM to the Instrument Panel Controller (IPC), A/C compressor requests sent from the Air Conditioning Programmer (ACP) to the PCM, or Climate Control information sent between the IPC and ACP. This shared information architecture also provides for the on-board self diagnostic capabilities of the computer control systems.
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