A diagnostic tool needs to distinguish the path used for its request from the path used for the response. An incorrect identifier arrangement can look like a silent controller.

Interpreting the evidence

Check the documented configuration and compare it with actual observed traffic from an authorised diagnostic session. Preserve the raw log so the request and response directions remain clear. Verify the setup before deciding that the module cannot communicate.

Keep this evidence

Include the tool profile and a capture of the attempted exchange.

Do not send guessed commands across arbitrary identifiers. Use the supported diagnostic configuration for the identified module.

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.