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OBD II Basics
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What Is OBD II?
On Board Diagnostics-Second Generation (OBD II), is a computerized system on 1996 & newer model year gasoline cars and light-duty trucks that monitors the operation of emissions-related components and systems.

This sophisticated system detects malfunctioning or deteriorating components and systems before more serious failures occur. Even before the driver of the vehicle might notice a problem, an OBD test identifies what repairs may be needed.

When a malfunction is detected by the vehicle's OBD II system, a diagnostic trouble code (DTC) is stored in the computer's memory and the "Check Engine" light comes on. The stored trouble codes (DTCs) can be read using an OBD II scan tool that plugs into the vehicles OBD II computer. Further diagnosis by a skilled automotive repair technician is needed to verify the problem and determine the most appropriate repairs.
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