OBD is an acronym for "On Board Diagnostics." As of 2010, OBD II (also known as OBD 2) is the standard set of diagnostic codes used by American-made automobile manufacturers. Some automakers use the minimum codes required by law, while others add many more to their vehicles.

History

OBD II codes were introduced in 1996 so car owners and drivers could more readily diagnose problems with their automobiles. OBD II is mandatory on vehicles made after 1996. This legislation was put into place by the Environmental Protection Agency (EPA).

Common Uses

OBD II codes are often used to understand why the "check engine" light goes on in cars. This light can go on for many reasons, and the codes help a car owner determine the issue.

Meaning

The meaning of each code can be found in he owner's manual of the vehicle containing the OBD II or online. Multiple resources are maintained on the Internet to help car owners diagnose and repair vehicle malfunctions.

Forums

If a car owner needs more information than is provided in her owner's manual or online documentation, she can post a query in an online forum. Other car owners and auto mechanics will read and possibly find a solution to the problem.

Warnings

When self-diagnosing OBD II codes, a car owner should exercise caution. Many issues that are brought to the owner's attention by the OBD II codes are fixable by "shadetree" mechanics. However, for more complex issues, a licensed mechanic should be consulted.

Source:

Autoengenuity: OE-Level Coverage (Enhanced Interfaces)

OBD Codes: What is OBD?

OBDII: Background