CSMT

Greetings. First post and a copy of what I posted on FB. This will not be news to most of you - but just to add to the thread. Greetings! First post and I don't want to start on a negative... but I have a 2022 C8 RS6 and it is a great car. Prior to this I had a RS5, then before than a C7 RS6 and so on. The subject of this post I think has been discussed in various groups (probably), I did a quick search in this group and did not come up with much - but forgive me if this is old news. Even if it is, it was worth a reminder of the catastrophic failure that might await anyone with a 2000 onwards car with the 48V alternator / mild hybrid / stop start system. I have this on my RS6, but it is not unique to RS cars. Before I describe the issue I should state that I think many of us get used to the "glitches" that these modern cars can have from time to time. The odd warning that comes up "suspension fault"- normally solved by stopping car, locking up and having a coffee, going back and starting - and all is good from then on. Last Thursday. Starts OK - Berkshire down to Exeter. Then back onto the M5 to head up towards Manchester. Came off at services for break, waiting to get back on M5 the car would not auto-start and I had a "stop start" failure yellow light. Onto the motorway. Shortly I then got a yellow "electrical system fault - take car to workshop". Still on the M5 I decided to proceed to next services. Stopped. Had a coffee. Back at the car the faults had cleared as expected (!). Onwards. Within 10 minutes the two faults appeared again, and a third fault "sports differential" - all so far with the 'visit workshop' advice. Then the car front screen began to mist up. The aircon was on, but the blower was confined to low speed. Opened the windows to clear the mist, little did I know that the car was slowing closing down. A few more miles up the M5 and more yellow warning - suspension failure, electrical system failure. By now I am getting worried but still wondering if these could be cleared with a longer break at services. And then RED warning - critical systems failure - stop vehicle now. Do I go into hard shoulder? What if it was a smart motorway. I note there is a services 2 miles ahead so I head for that using inside lane. Got into the lane off the motorway and managed to get into the parking area - looking for a space. Then the power steering failure occurred (red warning) - I am now in slow traffic flow, trying to turn right into a space and the steering is really heavy. Then there was the transmission failure (red warning) - and that was it. Car stopped and died. My hazard lights did work But why do drivers still beep and wave angrily at you as if I am doing this for fun?! Called Audi Assist (AA). Cannot fault the service here. The mobile AA came out. We managed to start / move the car by using a battery pack - just enough elec to get car safely parked - then it died again. We tried charging the 12 volt battery - but soon found it was not being charged by the 48V alternator (voltage is stepped down for charging). So it was a flat bed 2.5 hour trip back to Berkshire. The car is now at local Audi dealer. Findings so far (some from dealer, some from internet search). It is the 48V alternator / start stop system. It is covered under my standard 3 year warranty (good job it is expensive). Also covered under a little known (to many) 7 year unlimited miles special warranty. It is a known issue within Audi. I am not sure if the faulty / badly designed unit has been fixed, or if they are just replacing with current manufactured units - I think the 7 year warranty says is all.... So there we have it. If you have this 48V hybrid system on your Audi you might want to check the warranty. As far as I can tell there has been no recall in the UK. Yes - I could have stopped the car earlier on the motorway hard shoulder. But this all happened over a few minutes (the final failure phase). The car completely fails and it feels a dangerous situation to me - so please take note! Happier posts to follow in the future. (Ps still being fixed so I will report back when I have the car back).