RS7 Electrical Chaos: Multiple System Failures Puzzle Owner

I had nearly identical issues with my 2016 RS6. Unusual warning lights, system failures, and control modules going dark pointed to a compromised BUS system connection. The check engine light was also triggering intermittently without clear fault patterns. After using an OBD-II scan tool, multiple communication errors between control modules were detected. The root cause was a damaged wiring harness connector at the main control module, allowing moisture intrusion and signal degradation. The corroded connection was disrupting the entire CAN-BUS network. The fix required replacing the main harness connector and resealing the control module housing. This was definitely a serious issue since compromised BUS communications can affect multiple vehicle systems including engine management, safety features, and infotainment. A thorough diagnostic process using professional scan tools is essential here, as simply clearing codes wont solve the underlying connection problem. Given your symptoms match the classic signs of CAN-BUS communication failures, Id recommend having the wiring harness and control module connections inspected by a specialist who can properly test the network signals. The issue will likely worsen if left unaddressed, potentially leading to more system failures and warning light triggers.

Actually went through the same nightmare in my RS7 last year. The warning lights and system failures were driving me crazy. After multiple failed attempts, engine diagnostics revealed it was indeed a faulty CAN-BUS connector near the main control module. The scan tool showed communication errors across multiple systems. Had to get the entire wiring harness replaced along with some connector repairs. Service required a complete system reset afterward to clear all the stored error codes. Since the fix, all the unusual warning light issues have stopped and the control modules are working perfectly. Mind sharing how much the repair ended up costing you? Just curious if prices have changed since my fix. Also, has everything been running smoothly since the repair or have you noticed any new issues popping up?

The repair bill came to 155 Euro for fixing the faulty cable connection to the BUS system. The malfunction indicator lights and system failures completely stopped after the control unit connection was repaired. The engine diagnostics performed after the fix confirmed all communication systems were working properly. Running the scan tool showed no more error codes or warning lights since the repair. The infotainment system and all control modules have been functioning perfectly for several months now. When dealing with these types of electrical gremlins, having a proper diagnostic assessment really helps pinpoint the exact issue rather than just replacing parts hoping to solve the problem. The relatively low repair cost was a relief compared to the potential expense of replacing the entire wiring harness. Finding a mechanic who properly understood CAN-BUS diagnostics made all the difference in getting it fixed right the first time.

Let me share my repair experience. Finally took it to a specialized shop and what a difference it made. The mechanic immediately hooked up their professional scan tool and found multiple communication errors. Turned out the main control module had a damaged connector causing all those unusual warning signals and system failures. Total repair came to 1250 Euro including labor, new connectors, and complete diagnostic testing. More than the previous attempts but worth every cent since it actually fixed the problem. Been driving for 3 months now without a single warning light or system glitch. The infotainment works perfectly and all control modules respond normally. Such a relief after dealing with those electrical issues for so long. The specialist really knew their stuff about CAN-BUS systems and proper engine diagnostics. Should have gone there first instead of wasting 800 Euro at the other shop. Sometimes paying more for the right expertise saves money in the long run.