Diagnostic trouble codes (DTC), or OBD codes, are automotive computer codes stored by the on-board computer diagnostic system (OBD) in a vehicle. There are literally hundreds of different codes a Check Engine Light, ABS light, SUSPENSION light or etc light, can represent. While that sounds blaa blaa, a car diagnostics will give you will give you useful knowledge about a vehicle! Anyway, OBD codes may seem complex, but underneath the letters and numbers, you can identify the general cause of your lit Check Engine Light, allowing you to take the next necessary steps.
This program explains and is with most codes