U153E00 on Audi: Emergency call module and communication unit Recognition in mobile communications network not possible
Diagnostic trouble code U153E00 on Audi vehicles — what it means, the common
causes, and how to confirm the real fault before replacing parts.
What does U153E00 mean?
U153E00 indicates: Emergency call module and communication unit Recognition in mobile communications network not possible.
This relates to the Network / communication system.
Common causes of U153E00
Mobile communications network recognition not possible by emergency call module and communication unit J949
Faulty or missing aerial connection to emergency call module J949
Embedded SIM (e-SIM) fault within J533 (data bus diagnostic interface) requiring J533 replacement
Loss of mobile network signal (no GSM/UMTS/LTE/5G coverage available to module)
What to check (live data)
Mobile network registration status of J949
Aerial signal quality/connectivity at J949 aerial inputs
Ethernet communication status between J949 and other control units
CAN bus wake-up signal from central control unit for data bus communication J1273
Parts often involved in U153E00
Emergency call module control unit and communication unit J949
Data bus diagnostic interface J533 (contains non-replaceable e-SIM)
External mobile phone aerials connected to J949
Emergency call module aerial R263 (roof aerial)
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 U153E00 — 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.
U153E00 is a diagnostic trouble code: Emergency call module and communication unit Recognition in mobile communications network not possible.
What are the common causes of U153E00 on an Audi?
Common causes include: Mobile communications network recognition not possible by emergency call module and communication unit J949, Faulty or missing aerial connection to emergency call module J949, Embedded SIM (e-SIM) fault within J533 (data bus diagnostic interface) requiring J533 replacement, Loss of mobile network signal (no GSM/UMTS/LTE/5G coverage available to module). The exact cause depends on the vehicle — confirm it before replacing parts.
Can I keep driving an Audi with U153E00?
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 U153E00 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 U153E00 on your specific Audi.