U110B00 on Volkswagen: Light switch no communication (Unauthorized)
Diagnostic trouble code U110B00 on Volkswagen vehicles — what it means, the common
causes, and how to confirm the real fault before replacing parts.
What does U110B00 mean?
U110B00 indicates: Light switch no communication (Unauthorized).
This relates to the Network / communication system.
Common causes of U110B00
Short circuit on the LIN lead between Light Switch E1 and Vehicle Electrical System Control Module J519
Short circuit in the redundant back-up lead of the light switch
Loss of communication between Light Switch E1 and onboard supply control unit J519 via LIN bus
What to check (live data)
LIN bus communication signal between Light Switch E1 and J519
Redundant back-up lead ground signal (plausibility check of switch settings)
Parts often involved in U110B00
Light Switch E1
Vehicle Electrical System Control Module / Onboard Supply Control Module J519
LIN lead/wiring between E1 and J519
Redundant back-up lead
Operating unit for front door driver side EX55 (on applicable models where E1 is integrated)
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 U110B00 — 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.
U110B00 is a diagnostic trouble code: Light switch no communication (Unauthorized).
What are the common causes of U110B00 on a Volkswagen?
Common causes include: Short circuit on the LIN lead between Light Switch E1 and Vehicle Electrical System Control Module J519, Short circuit in the redundant back-up lead of the light switch, Loss of communication between Light Switch E1 and onboard supply control unit J519 via LIN bus. The exact cause depends on the vehicle — confirm it before replacing parts.
Can I keep driving a Volkswagen with U110B00?
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 U110B00 on a Volkswagen?
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 U110B00 on your specific Volkswagen.