Hi All,
New to doing my own work, I have a 2011 S4 with 180k on the crank giving me some recent issues. I was driving and I got a sports diff malfunction light, parked it and the car went completely dead - no lights, remote didn’t work. Opened the hood and the car had lights again, but no crank. It cycled between completely dead no lights to finally having crank and turning on. Scanned it with an OBD11 and got several codes which I have cleared and the only one that stays on now if the fiber optic most data bus - open circuit 00384. The other codes were P223700 )@ sensor positive current control circuit bank 1 sensor 1, P160200 Terminal 30 voltage supply low, P10A400 Regulating flap for intake air mechanical malfunction which it has had in the past, 01324 All wheel drive control module which is showing as a static code, U140100 Function restriction (tranny and AWD) due to over voltage, 01206 Ignition off signal duration (air conditioning fault), 00384 Fiber optic MOST data bus - open circuit, 00920 Heated outside mirror electrical error in circuit due to a broken mirror which I have just ordered a new one. I’m a little lost and have just ordered a Ross Tech VagCom scanner, but in the meantime I need to get this car running and was leaning it towards possible being a bad alternator or bad alternator regulator. For context, the battery is showing healthy, 14.6V while turned on and running, 12.7 when parked and ignition on. The car now turns on and has not given me any of the electrical issues such as being completely dead since towing it home. I have not tried driving it since I don’t want to get stuck and have to tow it back. Any thoughts would be greatly appreciated. Thanks!