U10E100 on Audi: Emergency call module no communication
Diagnostic trouble code U10E100 on Audi vehicles — what it means, the common
causes, and how to confirm the real fault before replacing parts.
What does U10E100 mean?
U10E100 indicates: Emergency call module no communication.
This relates to the Network / communication system.
Common causes of U10E100
Loss of communication with emergency call module control unit and communication unit J949
Fault on infotainment CAN bus connecting J949 to gateway/J533 or J794
Fault on Ethernet connection between J949 and J794
Wake-up signal fault on CAN bus connection to central control unit for data bus communication J1273
Faulty or missing e-SIM (embedded SIM) — requires replacement of data bus diagnostic interface J533
Discharged or faulty emergency battery within J949
What to check (live data)
Infotainment CAN bus communication status (500 kbit/s) between J949, J533 and J794
Ethernet connection status (1 Gbit/s) between J949 and J794
A2B automotive audio bus path status between J949 and microphone/J794
CAN bus wake-up signal from J1273 to J949
Emergency battery charge status within J949
Mobile network aerial signal availability (up to 4 external aerials; backup internal aerial)
Parts often involved in U10E100
Emergency call module control unit and communication unit J949
Data bus diagnostic interface J533 (required if e-SIM needs replacement)
Emergency battery (two special rechargeable batteries, fixed 7-year replacement interval)
Emergency call module aerial R263 (roof aerial)
Mobile communications aerials (LTE/5G/Wi-Fi/Bluetooth aerials connected to J949)
GPS aerial
Microphone front left R140
Microphone front right R141
Control unit 1 for information electronics J794
Central control unit for data bus communication J1273
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 U10E100 — 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.
U10E100 is a diagnostic trouble code: Emergency call module no communication.
What are the common causes of U10E100 on an Audi?
Common causes include: Loss of communication with emergency call module control unit and communication unit J949, Fault on infotainment CAN bus connecting J949 to gateway/J533 or J794, Fault on Ethernet connection between J949 and J794, Wake-up signal fault on CAN bus connection to central control unit for data bus communication J1273. The exact cause depends on the vehicle — confirm it before replacing parts.
Can I keep driving an Audi with U10E100?
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 U10E100 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 U10E100 on your specific Audi.