Communication Protocols KWP2000 (ISO 14230, ISO 15765), UDS (ISO 14229) and SAE J1939 in use
Protocols for programming interfaces have always been standardized whenever different test systems (e.g. in brand and independent repair shops) are to access vehicles or different ECUs have to be integrated into subsystems – requirements that are in fact always demanded nowadays!
UDS ISO 14229
UDS was developed with the goal of standardizing different implementations of the predecessor standards and new requirements to form one generally valid diagnostic protocol.
SAE J1939 was developed last century as a higher protocol layer for CAN. The aim was to develop standard communication mechanisms for trucks regardless of the OEM, engine/transmission manufacturer and test system manufacturer.
The experience with KWP2000 on the K-Line was already being transferred to CAN at the end of last century. For the first time, KWP2000 on CAN (ISO 15765) enabled the diagnostics and flash programming of a large number of ECUs via central diagnostic access.
KWP2000 on the K-Line was the first standardized diagnostic protocol used in Europe on a large scale. It defines all layers of the OSI reference model from physics through transport protocol to diagnostic services.
With Diagnostics over IP, diagnostic services introduced over UDS are used over TCP/IP and Ethernet. This makes considerably higher data rates available.
