Scan Tool Set-Up and Functionality: Overview

When performing powertrain diagnostics on On-Board Diagnostics II (OBD II) vehicles, the system may be checked by an off board tester referred to as a scan tool. Two types of scan tools are referenced here: the New Generation STAR (NGS) Tester scan tool and the Generic Scan Tool (GST). A GST has a capability that is standard across the automotive industry in the United States. However, to perform manufacturer-specific functions, a string of characters must be entered manually. If a NGS is used, those functions are selected from a menu.






The Villager is equipped with two Data Link Connectors (DLCs). The Powertrain Control Module (PCM) has two modes of communication. One for Generic Scan Tool (GST) use which has generic diagnostic capability that is mandated by the U.S. government and is accessed through the OBD II DLC. The other mode of communication is for expanded diagnostic capability and is accessed through the same fuse panel DLC that has been used in past years on the Villager. In order for the scan tool to communicate with the PCM in the proper mode the scan tool must be connected to the appropriate DLC (OBD II DLC for generic diagnostics and the fuse panel DLC for expanded diagnostics). If the NGS tester is used to communicate with the vehicle, an OBD II DLC cable or the fuse panel DLC cable must be connected to the tool. Refer to the NGS owner manual or scan tool manufacturer's manual for specific information.