Honda vehicles built after 1996 utilize an on-board diagnostic system know as OBD-II. This system of sensors works with the vehicle's engine computer to determine if the emissions systems are operating within proper tolerances. If a sensor determines a component is malfunctioning, it will trigger the "Check Engine" light in the dashboard. The OBD-II system can also provide a wealth of information about the performance of your engine, and warn you when service is required to avoid imminent failure.
Locate the OBD-II diagnostic port on your vehicle. On most models it is located below the dash or in the center console. Consult the owner's manual if you are having trouble locating it.
Connect the diagnostic cable to the OBD-II port.
Connect the diagnostic cable to the computer.
Launch the diagnostic software.
Turn the key to run, but do not start the engine. You will not be able to read most trouble codes while the engine is running.
Scan for trouble codes. Procedures for scanning vary according to which software you use. There is usually a button on the computer screen after you open the program that says something like "Search for Engine Codes." Click on it.
