Check the charging diagnosis video; i posted from youtube,before pulling it.
I was getting the same ECU voltage code plus a few other's. But mine wouldn't do anything. If you remember. I tried replacing parts to try to fix it. Also. If he is replacing parts. Are they OEM parts or after market one's. I learned the hard way about non factory parts. I understand that he was having this issue before replacing parts. But could that cause an issue because even though the parts are new. The picky VW may not like it. Also, after I got a VW scanner. I was able to clear the code's and then read again for the same code's. Also with my 2015 beetle. When I disconnect the battery. I have some lights come on that go away after driving a bit. My windows won't auto up and down for a bit either. The others I have to manually reset. I wonder how much of the systems he can read and if he has live data reading. That will tell him what the load is on the system among other things with the charging system. His is an 08 and mines a2015. But it might help him out with out throwing parts at it like I was doing. But my fix was to replace the ECU relay. But I had to replace the whole fuse block under the hood because the relay is built into it. 😒You can look up the codes; on the ross tech wiki:
For example that one; references, this:
- Battery Faulty
- Charging System Problem
So, I would do a hard reset; of the ecu and then, possibly, run down to a auto parts store and have the whole charging system tested, confirm everything is working as it should. As you noted, the trouble codes build up; they won't go away, until you clear them. Clear, test and take a test drive, then rescan, see what comes up.
👍 does it do the charging system? Like what the load % is and stuff like that? Live voltage being put out? If it does do the load %. I would turn everything on high and see what it is. Everything. Lights on high beam. Ac high, if you have heated seats. High. Everything. See what the load is with everything turned on. And what's on normally when driving every day. I know that our cars are different years. But the max load on mine with everything on high plus the radio system up high, is about 32% + - . Normal is around 28 % + -. And around 13.6 volts at idle. Not sure what you should have, but may give you a reference to look at.My scanner is a cheaper one so it does do live scanning. And yes, it is resetting each time I disconnect the cable. Everything is pointing towards the alternator and I believe I have some days off this week so one way or another I'll get it back on the road.
If it's possible. I would take the car to the auto parts store and have it checked out. Like billymade said, it's a pain to get off. No since in taking it out and just have to put it back in if it's good.I haven't had much of a chance to read through it yet. If I get a day off, I'm pulling the alternator and having it checked.