Audi S7 Starter Issues Point to Weak Battery/Charging

Had the exact same symptoms on my 2016 Audi S5 3.0T. After investigating, it turned out to be a charging system issue combined with a failing battery. The voltage drop during start attempts was the key indicator. First check the battery itself. Even with clean terminals, internal degradation can cause these symptoms. A proper load test will reveal battery health, basic voltage readings alone arent enough. If the battery tests okay, focus on the charging system. My case involved a faulty voltage regulator in the alternator that wasnt properly charging the battery. The wiring harness connected to the alternator also showed signs of wear, creating additional resistance in the circuit. Common failure points to investigate: Alternator voltage regulator, Short circuit in the main power cables, Loose connections in the fuse box, Corroded ground straps This was a serious repair requiring alternator replacement and wiring harness repair. The symptoms will only get worse if not addressed. Getting it diagnosed with proper equipment is essential, as these electrical issues can cascade into other systems. The starter drawing excessive current during startup is often a symptom rather than the root cause. Focus on the charging system components first before replacing other parts.

Thanks for sharing your experience. I had the same problem with my S7 last year. The electrical fault turned out to be a combination of issues just like in your case. The wiring harness near the alternator was damaged and the battery was on its last legs. Did you keep track of the total repair costs? Also wondering if any other electrical problems popped up since getting it fixed? My mechanic mentioned these issues can sometimes signal more extensive problems in the circuit breaker system.

Glad I could help identify the issue. After seeing the mechanic, the Terminal 30 continuous plus problem was completely resolved by fixing the heavily discharged battery. Total cost came to 290 Euro which included diagnostic testing and replacement. The wiring harness repair from my previous post has held up perfectly with no new electrical faults appearing. The short circuit issues I initially experienced havent returned either. Key is that they did a thorough check of the entire electrical system including the fuse box and ignition switch connections while they had it apart. A proper diagnosis really made the difference, catching failing components before they cause cascading problems saved money in the long run. Would definitely recommend getting any voltage drop issues checked promptly rather than waiting for complete failure. The car starts perfectly now, even in cold conditions, and the charging system maintains proper voltage. No warning lights or unusual electrical behavior since the repair.

I finally took it to a trusted mechanic last week. The diagnosis confirmed the charging system problems we discussed. My alternator voltage regulator was shot and there was significant wear on the wiring harness connection points. The total repair came to 850 Euro including parts and labor. They replaced the alternator, repaired sections of the wiring harness, and installed a new high-performance battery since the old one was damaged from irregular charging. The circuit breaker system checked out fine, thankfully. No other electrical gremlins have shown up since the repair. The starter motor now engages instantly and the voltage stays rock steady during cranking. Honestly relieved to have it properly fixed. The car starts perfectly every time now and all electrical systems are working as they should. Worth every cent to have it done right instead of trying cheaper partial fixes. Thanks for helping point me in the right direction. Would have wasted time and money chasing the wrong problems without the advice here.