Diagnostic “Scan” tools are the most versatile and effective way to isolate circuit faults, identify improper component operation, and otherwise troubleshoot the electrical circuits of the engine management system.
Two “Scan” tools are available to General Motors technicians (figure 6-10): the hand-held Tech 1 and the T100 Computerized Automotive Maintenance System (CAMS).
Both systems offer Diagnostic Trouble Code (DTC) capabilities. The Tech 1, however, is more versatile. It can be used inside the vehicle and on road-tests for capturing intermittents.
Tech 1 usage is covered in detail later in this section.
