ISO 14229:2006 specifies data link independent requirements of diagnostic services, which allow a diagnostic tester (client) to control diagnostic functions in an on-vehicle Electronic Control Unit (server) such as an electronic fuel injection, automatic gear box, anti-lock braking system, etc. connected on a serial data link embedded in a road vehicle. It specifies generic services, which allow the diagnostic tester (client) to stop or to resume non-diagnostic message transmission on the data link. ISO 14229:2006 does not apply to non-diagnostic message transmission, or to use of the communication data link between two Electronic Control Units. It does not specify any implementation requirements.

The vehicle diagnostic architecture of ISO 14229:2006 applies to a single tester (client) that may be temporarily or permanently connected to the on-vehicle diagnostic data link and several on-vehicle Electronic Control Units (servers) connected directly or indirectly.