RS6 Immobilizer Fault Stops Engine From Running

Had a similar situation with my 2016 Audi S6. The security light would flash constantly and the engine would die right after starting. The car immobilizer system was preventing normal operation due to key signal issues. The root cause turned out to be incorrect key programming after a battery replacement. The immobilizer system lost synchronization with the key transponder. While this sounds minor, it required specialized diagnostic equipment to properly reset and reprogram. A proper fix involved: Full diagnostic scan to verify immobilizer fault codes, Resetting the immobilizer control module, Reprogramming both main and spare keys, Testing the remote start function after programming This is definitely a job for an authorized service center with proper diagnostic tools. The immobilizer system is tied to critical security features, so DIY attempts often make things worse. The repair itself isnt extremely complex, but requires specific equipment and expertise. Watch out for shops suggesting parts replacement before trying reprogramming. In most cases, its a programming issue rather than failed components.

Thanks for the detailed writeup on the anti-theft system issue. My RS6 had nearly identical symptoms last year with the security light flashing and engine dying. The immobilizer fault turned out to be fixable through key programming, just as you described. Just wondering, what did the authorized dealer charge you for the full fix? My repair bill came to 450 Euro including diagnostics, but prices seem to vary. Also curious if youve had any repeat issues since getting it sorted?

Thanks for asking about the repair costs. After seeing the mechanic, the immobilizer fault was completely resolved with a simple key programming fix. The total bill came to just 45 Euro, which was quite reasonable compared to your experience. The anti-theft system has worked flawlessly since the repair. No more issues with the security light flashing or the engine cutting out. The key signal is now properly synchronized with the immobilizer control module. This really shows how important it is to find a shop that starts with programming diagnostics before jumping to expensive parts replacements. Often these immobilizer faults can be fixed through reprogramming rather than component replacement. The car electronics have been running perfectly for months now without any repeat problems. Its worth noting that proper diagnosis saved both time and money in this case.

I checked into another garage based on these insights and got much better service. The technician immediately suspected a key programming issue when I described the immobilizer fault symptoms. They connected their diagnostic equipment and confirmed the immobilizer control module needed resynchronization. The whole repair took under an hour and cost 175 Euro, way less than my previous shop quoted for parts replacement. Its been 3 months now with zero issues. The ignition control system works perfectly, no more security lights or stalling. Really glad I got a second opinion instead of paying for unnecessary repairs. Sometimes the simplest solution is the right one when it comes to car electronics.