OTX - ISO 13209

OTX (Open Test sequence eXchange format) is an international standard and describes a sequence language for exchanging diagnostic and test processes in the automotive industry.


The standard allows diagnostic sequences to simultaneously describe enough implementation details, so that these can be carried out both on specification level and display. In addition, OTX directly supports variant management, which makes the adaptation of the processes much easier.


The standard consists of three parts:

  • ISO 13209-1 describes the motivation and applications.
  • ISO 13209-2 defines the core language. This includes all language elements incl. basic variable types, prozedure declarations, control structures, expansion options and troubleshooting. The core language is kept generic and therefore also suitable for applications outside of the automotive industry.
  • ISO 13209-3 defines the standardized extensions (OTX Interface Definitions), which provide new instructions and data types. These are, for example, tailored for diagnostic communication with the control units of vehicles or for interaction with the user.