Audi S7 Keyless Entry Failure Points to Faulty Antenna

Having faced a similar issue with my 2018 Audi S6, I can share my experience as someone with some automotive electronics background. The symptoms you describe match exactly what I encountered. The car radio worked perfectly, but the keyless functions failed completely. After initial diagnosis, it turned out the vehicle antenna connector had developed corrosion, causing signal interference with the key detection system. The fix involved: Complete diagnostic scan, Removal of front bumper trim, Cleaning and replacement of antenna connectors, System reset and coding Total repair cost was 95 Euro, mostly labor since the issue was a faulty cable connection rather than a complete antenna repair. To provide more specific advice for your case, could you share: Have you noticed any water exposure in the front bumper area? Are there any specific error codes showing? Did this start gradually or suddenly? Have you tried using the backup key blade? A proper diagnostic scan would confirm if your issue matches what I experienced. While the radio signal might be fine, the separate antenna system for keyless entry often requires different troubleshooting steps.

Last service at 116031 KM completed just two weeks ago. After consulting with another owner in the forum, I noticed the keyless entry problem might be more widespread than initially thought. The antenna replacement solved their issues completely, though their symptoms were a bit different. The fm antenna and radio functions in my car still work perfectly, suggesting the keyless entry antenna mount is indeed the likely culprit. To answer your questions: No visible water damage in the bumper area, Error code P0513 shows consistently, Issue started gradually over 2 weeks, Emergency key blade works normally The antenna repair quote I received seems much higher at 450 Euro. Would appreciate feedback on whether this pricing seems reasonable, given the scope of work needed.

Glad you provided those details about your situation. The error code P0513 matches exactly what I encountered before my repair. While my initial repair was cheaper at 95 Euro, I should mention I later discovered the corroded connector was just a symptom of a larger issue. The full antenna mount assembly eventually needed replacement, pushing the total cost closer to 400 Euro. Looking at your 450 Euro quote, its actually quite reasonable for a complete antenna system replacement. The labor involved in accessing the front bumper antenna assembly and recoding the system justifies the cost. My lower initial repair only temporarily resolved the signal interference issues. Based on your gradual onset of symptoms and working radio functions, your diagnosis aligns perfectly with the vehicle antenna problems many of us have experienced. The fact that your emergency key works normally further confirms the issue lies with the keyless system rather than the immobilizer. The mileage you mentioned is around where these antenna mount issues commonly surface. Since your FM antenna works fine but the keyless functions are failing, its almost certainly the dedicated key detection antenna causing the problem. Rather than trying intermediate fixes like I initially did, going for the complete antenna replacement might save money in the long run. The signal interference will likely worsen over time if left partially repaired.

Thank you for sharing those details about your P0513 code and the gradual onset. My situation definitely seems less severe compared to what you experienced. The 450 Euro quote initially shocked me, but after reading about your repair journey and the eventual need for complete replacement, it makes more sense to address everything properly now. I will schedule the full antenna repair next week. The deteriorating signal range and complete failure of keyless functions really need fixing, especially given the mileage. At least the car radio and other systems still work normally, which helps confirm the issue is isolated to the keyless entry antenna system. Your feedback about avoiding temporary fixes probably saved me from wasting money on partial repairs. Will update the forum once the work is completed in case others encounter similar symptoms with their keyless systems. Thanks again for the detailed insights and repair cost comparison, really helped clarify the best path forward.