The Introduction to On-Board Diagnostics II (OBDII): Hands-On Diagnostic Simulation CD-ROM utilizes an interactive approach to lead users through ten trouble-code scenarios (problems). Users will have to choose what tool, meter, scope, scanner, or other diagnostic aid to use as they proceed through specific troubleshooting sequences. The CD allows users to learn "quick hit" troubleshooting tricks, and learn how to diagnose problems even when there is no stored OBDII trouble code. In addition, the users will learn how to diagnose and solve problems in situations when the trouble code is set by a basic mechanical fault rather than a failure of the indicated component. These real-time, interactive practice exercises effectively simulate the use of actual test equipment so that users learn to choose the appropriate diagnostic aid for effective troubleshooting.