Did the stereo kill the battery, or did the battery die a natural, dignified death?


New member
Sep 15, 2020
2015 Passat TSI SE
Hi. I'm brand new. To life. So pink and startled.

Okay, I've done some digging on this here today, found bits and pieces of somewhat related stuff, but I thought I'd state as clearly as I could what I'm specifically dealing with, and see if anyone has any thoughts:

- 2015 Passat TDI SEL (required by law to state that it's a manual, though it's not really pertinent to the situation.)
- Love it.
- Wanted new stereo with Android Auto
- Installed Sony AX3000
- Used PAC RP4-VW11
- All groovy, but no radio or backup camera.
- Discovered I need adapters for those.
- No prob, ordered them.
- Enjoyed driving with maps, Spotify, etc for two days.
- Middle of the day today battery dies.
- Jumped it, kept it running about 2hrs, let it sit an hour, dead again.
- Charged it up.
- Unable to chalk up new stereo > battery dying as coincidence
- Google a lot, call PAC, test battery (low without charge, about 10.5v) and alternator (good, about 14v at battery when running.)
- Eventually pull stereo to inspect wiring. Was going to have to anyway when new adapters arrive.
- Nothing glaring on wiring connections.
- Replaced factory unit to see if battery drain goes away.
- Now backup camera not working on factory unit.

So I'm scratching my head wondering if it's possible that my battery just decided to die now, and it has nothing to do with me replacing the stereo three days prior.. Seems too good to be true. I'll roll the dice and drive it to work tomorrow and see what happens after it sits for a few hours.

(Also, why the hell isn't the backup camera working on the original unit? Replaced all the same connections.. Maybe I didn't get the 26pin connector in sufficiently...)

Battery is probably the original. I certainly haven't replaced it in the 2yrs I've owned the car. Maybe it is just its time.

Thanks for reading. Sometimes we just need to be heard, right?