Data Link Connector: Description and Operation

1993 Cadillac Fleetwood Brougham V8-350 5.7LSECTION Description and Operation



Diagnostic Terminal Connector:






PURPOSE
The provision for communicating is the Data Link Connector (DLC). Serial Data is a single wire line that the Engine Control Module (ECM) uses to communicate and share information with other systems. All major components (SIR, CCM, HVAC, 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.

TESTING
The technician performs diagnostic testing and reads Diagnostic Trouble Codes (DTC) by jumpering terminals on the DLC.

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 DLC connector and is used for hookup of test equipment.





RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.