C 2500 Suburban 2WD V8-454 7.4L (1994)
Data Link Connector: Description and Operation
ALDL Connector
Purpose
The Data Link Connector (DLC) provides a means of communicating with the control module concerning engine and transmission operating parameters
and accessing Diagnostic Trouble Codes (DTC).
Operation
The control module communicates a variety of information through the Serial Data Line (DLC terminal "M"). The data is transmitted at a high frequency
which requires a Tech 1 diagnostic computer (scan) tool for interpretation. There are several other non-OEM scan tools available for displaying the same
information.
