RS3 Immobilizer Kill Switch Causes Dead Engine Starts

The immobilizer fault you describe matches what happened with my 2017 S4. The key signal would allow initial start but the immobilizer system would cut fuel delivery within seconds. This required specialized diagnostic equipment to properly resolve. The issue stemmed from a corrupted key programming sequence in the immobilizer control module, not a mechanical problem. A regular scanner cannot properly diagnose these systems. The fix involved: Full immobilizer system diagnostic, Control module reprogramming, Key resynchronization, Verification of the remote start functionality This is considered a serious electrical issue that needs dealer-level equipment. Regular shops often struggle with immobilizer bypass procedures since they lack access to proper security protocols. The immobilizer fault needs to be cleared from both the key and the car computer to restore normal operation. I would strongly recommend having this addressed at a shop with manufacturer-certified diagnostic capabilities. While my repair was successful, attempting multiple fixes at shops without proper equipment risks further programming conflicts.

Thanks for sharing your S4 experience. This exact security light and immobilizer fault happened on my RS3 last winter. The symptoms were identical, brief start followed by immediate stall. Really frustrating since the anti-theft system was preventing normal operation. Did you track how much the dealer charged for the key programming and system reset? My repair included similar steps but curious about pricing across different places. Also wondering if youve had any recurring issues since getting it fixed? My system has been stable but always good to know what to watch for.

Glad I could help with the immobilizer fault info. The key programming fix for my S4 was surprisingly affordable at just 45 Euro for the complete service. Since having the security system reprogrammed, the anti-theft system has worked flawlessly with no recurring issues. The shop used their specialized diagnostic equipment to properly reset the immobilizer control module and resynchronize the key. Most importantly, they cleared all the stored fault codes that were causing the car to stall. The ignition control system now works perfectly every time. Looking back, attempting fixes at regular shops without proper security system capabilities would have likely cost more in the long run. The manufacturer-certified equipment made a huge difference in properly resolving the immobilizer fault the first time. Going on 6 months now with zero problems, no security lights, no stalling, just normal operation. The key programming solution seems to have fully resolved the underlying issue.

After reading about similar immobilizer problems, I finally took my RS3 to a certified shop that specializes in car electronics. The security light issue was exactly as others described, a programming conflict in the immobilizer system. The shop had the right diagnostic equipment and completed: Full system scan, Immobilizer bypass and reset, New key programming sequence, Complete verification testing Total cost came to 320 Euro but worth every cent since the car now starts and runs perfectly. No more stalling or security light warnings. The specialized diagnostic tools they used made all the difference compared to previous failed repair attempts. Been driving it for 3 months now without any ignition control issues. Really glad I found a shop with proper security system experience instead of continuing with basic mechanics who lacked the right equipment. The car runs like new again.