Automotive dictionary

Explains vocabulary and abbreviations used in Automotive

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OBD is a generic term for On-Board Diagnostics. A distinction is drawn between OBD, OBD II, and EOBD (European OBD). OBD is a "function" of the vehicle. It monitors the vehicle's emissions-related components in order to meet legislated restrictions for the life­ cycle of the vehicle. OBD is not limited to exhaust relevant components; it contains other functions such as gas tank leakage tests.

OBD scan tool

An OBD scan tool is a tester that is used for diagnostic communication with the vehicle's OBD system. OBD scan tools are specified in SAE J1978.

ODX category

The ODX categories are part of the ODX data model and are the uppermost level of an ODX database. Every object of the type category (ODX category) is described in an individual XML file.

ODX checker

The ODX checker is a computer program or program module that checks if a given ODX database meets the checker rules of the ODX standard.

ODX data pool

An ODX data pool is a frame that allows visibility of all ODX data parts that are reachable by ODX links. For example, the data pool of a Diag-Layer A contains the services (X) of the Diag-Layer A. If Diag-Layer A references another Diag-Layer B, all services (Y) that are defined in the Diag-Layer B become a part of the data pool of Diag-Layer A that now contains the services {X,Y}. An ODX database can contain several data pools.

ODX database

An ODX database is formed by ODX objects that can be interlinked via ODX-links or short-name references and defines a data pool. All objects in a database have to be unique. Compare to ODX data pool.

ODX filter

An ODX filter is a subset of the element data block. ODX filters reduce the visibility of data contained in a flash data file.

ODX instance

An ODX instance is a self-contained set of ODX data such as a Diag-Layer of the type protocol or a file that contains an object of category flash. Usually, instances are stored in separated files.

ODX segment

An ODX segment is an ODX element that describes a part of a logical software component. The ODX segment should not be confused with a segment of an in-vehicle network.

ODX session

An ODX session is an ODX element that contains all information about the data of the upload and download of logical software components. The ODX session should not be con­ fused with a diagnostic session.


The ODX-link is the basis of the reference concept for data in an ODX data pool. Every object that is a target of an ODX-link has to have a unique identifier. For example, targets of ODX-links are layers, diagnostic services, data type descriptions, and physical values. These references are called PROTOCOL-REF, LAYER-REF, IMPORT-REF, DOP-REF, and so on. ODX-Iinks help avoid redundancies, especially for objects that will be used more than once. See also short-name reference.


OEM is short for Original Equipment Manufacturer, often used as a synonym for vehicle manufacturers.


This is a consortium founded as OSEK by German vehicle manufacturers, suppliers, soft­ware houses, and the University of Karlsruhe and merged with the French initiative VDX. OSEK/VDX specifies a real-time operating system (OSEK-OS) for ECUs (see


OSI is short for Open Systems Interconnection. The OSI model is specified in ISO 7498-1.

Source Christoph Marscholik and Peter Subke (2008) - Road vehicles, Diagnostic communication -