[ Home ] [ Download @Sourceforge ] [ Documentation ]
[ Source code @github [primary] ]

This document is here to collect everything we can find about OBD-II, it's various interfaces, protocols and layers.

OBD-II is a standard for vehicle diagnostics relating to emissions implemented on all US vehicles since the mid 1990s. Europe has just introduced a standard called EOBD which is basically the same.

• A list of the interfaces that we believe ScanTool will support.
• A diagram that describes the OBD-II protocol's various component layers and sub-specifications. (source: SAE J1979)
• Another diagram of the OBD-II layers. (source: SSF 14230-2)
• A Description of the OSI seven layer interconnect model on which freediag's implementation rests.
• Documentation of the pinout of the OBD-II connector - along with which pins each sub-protocol supports.
• How to know whether your car fully supports OBD.
• A list of results obtained with various cars, various interface cables and various versions of scantool.