Hombre XS Space Cab L4-2.2L CPC (1997)
Data Link Connector: Description and Operation
Class II Serial Data
U.S. Federal regulations require that all automobile manufacturers establish a common communications system. This vehicle utilizes the Class II
communications system. Each bit of information can have one of two lengths: long or short. This allows the vehicle wiring to be reduced by the
transmission and reception of the multiple signals over a single wire. The messages which are carried on Class II data streams are also prioritized.
In other words, if two messages attempt to establish communications on the data line at the same time only the message with the higher priority
will continue. The device with the lower priority message must wait. The most significant result of this regulation is that the regulation provides
the scan tool manufacturers with the capability of accessing the data from any make or model vehicle sold in the United States.
Data Link Connector (DLC)
The provision for communicating with the control module is a Data Link Connector (DLC). The DLC is usually located under the instrument
panel. The DLC is used in order to connect to a scan tool. Some common uses of the scan tool are listed below:
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Identifying stored Diagnostic Trouble Codes (DTCs)
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Clearing the DTCs
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Performing the output control tests Reading the serial data
