The Data Link Connector (DLC) is installed in the vehicle so a functional check of the engine’s electronic control system can be made at the factory. The DLC also allows service technicians to use the PCM’s self-diagnostic system to check the status of various components used in the engine’s electronic control system (figure 5-59). This can be accomplished by grounding the terminals in the DLC or by using a “Scan” tool.
All voltage and resistance checks at the DLC connector must be checked with a high impedance (10 megaohm) digital volt ohmmeter to prevent damage to the vehicle’s electronic components.
