For on-board diagnostics, the OBD-2 standard defines the exchange of specific vehicle parameters

The client makes a request on the connected control units (ECUs) in the vehicle to which one or several ECUs are answering. As part of OBD-2, the ISO 15765-4 standard describes the CAN bus as a transmission option.
The PCAN-OBD-2 API implements the functionality of the standard on the basis of 15 functions. They are categorized in Tester Allocation, Configuration, Information, Services, and Communication.
According to ISO 15765-4, OBD-2 is based on UDS. Analog to this, PCAN-OBD-2 uses the PCAN-UDS programming interface for the exchange of diagnostic data.