As of 2010, OBD-II refers to the type of engine diagnostic system employed by most modern car manufacturers, including Subaru. Subaru Outbacks have used the OBD-II system since 1996. OBD-II allows users to connect a computer diagnostic tool directly to the Subaru Outback computer for quick and easy diagnosis of engine codes. When your Subaru Outback's check engine light comes on, connect an OBD-II device to your diagnostic system to find out what is wrong.
Remove the lower dashboard panel on the driver side of your Subaru Outback. It is the panel located in the space between the bottom of your steering wheel and your gas and brake pedals. The panel should simply pull off.
Look for the OBD-II data link connector (DLC). The connector will have 16 pins arranged in two rows of 8. It will be unplugged and should resemble the connection on your OBD-II scanner.
Plug your OBD-II scanner into the DLC on your car and turn the scanner on and your car on. You do not need to start your car; simply turn the key to the "On" position.
Read the code displayed the scanner and record it. Some scanners will evaluate the code for you, while others require cross-checking with a full service manual made for your specific year of Subaru Outback.