U146700 on Audi: Data bus Service not available (Unauthorized)
Diagnostic trouble code U146700 on Audi vehicles — what it means, the common
causes, and how to confirm the real fault before replacing parts.
What does U146700 mean?
U146700 indicates: Data bus Service not available (Unauthorized).
This relates to the Network / communication system.
Common causes of U146700
Unauthorised access to sensitive vehicle data blocked by the diagnostic firewall in J533
Diagnostic firewall active because vehicle has travelled more than 200 km with bonnet closed (firewall reactivated after 20 km with bonnet closed)
Write service attempted while diagnostic firewall is active (all write services disabled by default)
What to check (live data)
Gateway measuring value blocks via VAS 5051 (Address Word 19 on later Audi models; Address Word 17 on earlier models via instrument cluster or vehicle electrical system control module)
Parts often involved in U146700
Data bus diagnostic interface J533
Don't replace parts until the root cause is confirmed — many of these codes are caused by wiring, a connector or an upstream fault, not the part itself.
Get the confirmed root cause for U146700 — on YOUR vehicle
A code is a symptom, not a diagnosis. AutoDX Pro cross-checks several
independent assessments, pinpoints the actual root cause, gives you the
exact tests to confirm it, and shows the parts — only after the cause is
confirmed. Reads your scan-tool photo and decodes your VIN with open
recalls.
U146700 is a diagnostic trouble code: Data bus Service not available (Unauthorized).
What are the common causes of U146700 on an Audi?
Common causes include: Unauthorised access to sensitive vehicle data blocked by the diagnostic firewall in J533, Diagnostic firewall active because vehicle has travelled more than 200 km with bonnet closed (firewall reactivated after 20 km with bonnet closed), Write service attempted while diagnostic firewall is active (all write services disabled by default). The exact cause depends on the vehicle — confirm it before replacing parts.
Can I keep driving an Audi with U146700?
It depends on the fault and your symptoms. Some causes are minor, others can damage components or affect safety. Get the root cause confirmed before deciding.
How do I fix U146700 on an Audi?
Confirm the actual root cause with targeted tests first, then replace only the part that's at fault. AutoDX Pro gives you the root cause, the exact tests, and the parts for U146700 on your specific Audi.