[Fominas]

Hello,

Got a dumb issue of the car overcharging to 15.3-15,7v. The interesting part is that when the car starts up, the alternator is charging to 14,3-14,8 range which seems normal, but after 15-20 seconds it goes to the 15,3-15,7 range and stays there, which does not sound normal to me. Initially the car had a bad battery when i bought it, but after replacing and recoding it through NCSEXPERT the overcharging remained.

Then i changed the voltage regulator on the alternator and nothing really changed, no fault codes or anything else as well, what could i check next?

There are no apparent issues, car is driving perfectly fine, everything seems to work, but i am a bit worried about killing the new battery with high voltage.

Vehicle in question is BMW e92 330D with the M57 engine.

[lnxguy]

If you've already changed out the voltage regulator the only next step is the alternator itself.

[ptpending]

if you have:
1. battery option coded as NON-AGM battery,
2. ibs sensor,
3. battery is discharged
4. cold weather outside,
then there could be short time voltage up to 15.8, this is to shake the discharged battery
so check the voltage before start, if its lower than 12.6 v, then car electronics can do that, but for short period
you can try to code battery as AGM, and then diesel electronics will limit this shake up to 14.8