RS6 ECU Glitch Triggers Low Power Mode and Error Codes

Had similar control system issues with my RS4 (2020) last month. The symptoms matched yours, reduced engine performance and stored error codes. After running extensive car diagnostics, it turned out the main relay was causing ECU communication problems. The ECU repair involved replacing the main relay unit since it was intermittently failing to provide stable power to the engine management system. This is actually a serious issue that can lead to complete system failure if left unchecked. When the main relay malfunctions, it disrupts critical signals between the ECU and engine components. The repair required specialized testing equipment to verify the new relay was working correctly after installation. The system reset and subsequent road testing confirmed all systems were back to normal operation. This kind of electronics issue definitely needs attention from a certified specialist who understands modern automotive control systems. Given your RS6 is nearly new, would recommend having it checked at a certified service center since they have proper diagnostic tools and access to latest technical bulletins.

Thanks for sharing your experience. Your relay issue sounds exactly like what I am experiencing. I have scheduled a diagnostic appointment with a certified shop that specializes in vehicle electronics and ECU repairs. Just curious, do you remember the total repair cost for fixing the relay and ECU problems? Also, has everything been running smoothly since the repair, or have you noticed any other electrical glitches? The computer module issues on these modern cars can be tricky, so I want to make sure I am prepared for what might come up during my service visit.

Good news, since taking my RS4 to the mechanic and getting the engine control system fixed, everything has been running perfectly. The main relay replacement resolved all ECU problems completely. Total cost was 120 Euro for parts and labor, which seemed reasonable given the specialized car diagnostics work involved. The engine performance returned to normal immediately after the repair. No more error codes or electrical issues have occurred in the months since. The control system now functions exactly as it should, with smooth power delivery and proper ECU communication. Based on my experience, your scheduled visit to a specialized shop is definitely the right move. Their expertise with automotive electronics should help identify and resolve the issue quickly, especially since your symptoms match what I encountered.

Thanks for the advice. I took my RS6 to the certified shop today. After thorough car diagnostics, they found similar relay issues affecting the engine control system. The technician showed me how the faulty relay was disrupting ECU communication. Total repair came to 180 Euro including parts and labor. The automotive electronics specialist also performed a complete system reset and ran multiple tests to ensure everything was working properly. Engine performance is now back to normal, no more power issues or error codes. The shop was extremely professional and walked me through the entire diagnostic process. Their expertise with control systems definitely made a difference compared to my previous mechanic. Really glad I chose a certified specialist for this repair.