S8 SOS System Glitch Returns Despite Multiple Repairs

Had a similar emergency call system malfunction in my 2017 A7 3.0T. The diagnostic codes pointed to a faulty connection between the telematics control module and the cellular antenna. A system reset did not resolve the issue. The root cause was corrosion in the main wiring harness connector under the rear deck. The moisture intrusion led to intermittent call failure and persistent warning messages. This explained why previous quick fixes only worked temporarily. The repair required removing interior trim panels to access and replace the complete wiring harness section along with the connector assembly. After installation, the module needed proper initialization and coding to fully restore functionality. This was classified as a safety-critical repair since the emergency call feature is a mandated system. If your S8 shows similar symptoms, checking the wiring harness connections should be prioritized over simple electronic fixes. The diagnostic codes should specifically indicate if there are communication faults between components. A thorough inspection of all related connections and proper component testing will help prevent the issue from recurring. Quick repairs targeting only the error messages often miss underlying wiring problems.

Thanks for sharing those details. I had an identical issue with my S8 last year where the emergency call system kept failing. The automotive electronics shop found corroded wiring and a failing telematics control module. The car safety systems are working perfectly since the repair with no warning lights or error codes. Would you mind sharing what the total repair cost was in your case? Also curious if you've experienced any other electrical gremlins since getting it fixed? Always helpful to know what to watch out for with these complex systems.

Glad your S8 is running well now. The telematics repair on my A7 cost 95 Euro to fix the faulty cable connection. The diagnostic codes cleared immediately after the repair and the emergency call system has worked flawlessly since then. The malfunction warning lights disappeared completely after they replaced the corroded wiring harness connector. No other electrical issues have surfaced in the months following the repair. The call failure problems that were so frustrating before are now completely resolved. Make sure to keep an eye on your system status through the vehicle menu, it should show all telematics functions as fully operational now. Regular checks can help catch any potential issues early before they develop into bigger problems.

Great news that others had similar experiences to share. After the constant SOS signal failures on my S8, I finally took it to a certified electronics specialist last week. They did a complete diagnostic scan and found both damaged wiring and a faulty control module like others mentioned. The repair took two days since they had to carefully access and replace sections of the wiring harness. Total cost came to 780 Euro including parts and labor. Bit expensive but worth it to have the emergency call system working reliably again. No more malfunction warnings or error messages in the dash. Been driving for a week now with zero issues. The technician explained they see this problem regularly on these models due to moisture getting into the connectors over time. Going to have them do preventative checks during regular service from now on.