VAG-COM Diagnostic Scan T5 Multivan, Year 2004

Hello everyone,

I'm having a problem with my bus:

I can only read the error codes with the ignition turned on.

Communication is not possible while the engine is running, and therefore, certain measurement data blocks cannot be accessed.

After starting, the diagnostic function is not available again until 2 hours later.

The error memory indicates that no errors were found.

VW is at a loss.

I use VAG-COM in its licensed version and have already used it to diagnose many vehicles.

"Can anyone offer any suggestions? I would be grateful for any information, no matter how small."

Best regards to everyone, Mario.