Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Data Link Connector: Description and Operation

Figure 1 Terminal Arrangement In Connector:






This connector is used in the assembly plant to connect a computer for checking of the system to see that it is functioning properly before shipping the vehicle. To obtain trouble codes with the ignition switch on and the engine either stopped or running the "test" terminal in this connector should be grounded. The "test" terminal should be ungrounded when starting the engine or the "Check Engine" lamp will not function properly.