Flow-control traffic belongs to a particular transfer. Receiving it outside the expected state can indicate a mismatched exchange or tool configuration.

Interpreting the evidence

Check the diagnostic identifiers, addressing mode and preceding request sequence. Establish whether another diagnostic application was active and whether the log combines separate sessions. The aim is to identify which transfer the message belongs to before treating it as faulty vehicle behaviour.

Keep this evidence

Send an unedited log with timestamps and the list of connected diagnostic tools.

Only one controlled, supported diagnostic workflow should be used for programming. Competing sessions can make evidence difficult to interpret.

Speak to AXION

For CAN-bus and vehicle-network diagnostics, send your vehicle details and fault report. Workshop assessment is in Didcot, Oxfordshire. Suitable postal or remote work is confirmed before booking.

Technical background from python-can-isotp. The referenced design explains the principle; the vehicle-specific procedure determines the repair.