[LittleSos20]

Hi all
Long time lurker here looking for some help I haven’t found a specific answer for.

I’ve recently replaced alternator voltage regulator, OFHG and now IBS.

The problem I’m having is now my battery is not charging while engine running.

BimmerLink is showing IBS voltage 14V
Battery voltage was showing 66V!!! In desperation i registered my old battery again as new and now battery voltage shows 13.5 in BimmerLink

BUT I don’t believe it’s correct

Multimeter shows 12.3V testing across the following points
1. Battery terminals
2. Jump start terminal to under bonnet ground terminal
3. Alternator to ground terminal
3. Ground terminal to positive battery terminal

I feel like this started when I changed out IBS, I’ve tried disconnecting IBS, nothing changes

I’m getting no codes

Battery not charging and multimeter showing 12ish V normally = alternator dead.

BUT why is OBD showing voltage of circa 14V when symptoms and my multimeter tests prove this to be wrong???

and IF the cars systems believe this is correct voltage could it be stopping alternator from chargbatery to protect battery life???

Is there anything I’ve missed before I pull the trigger and get a new alternator as they aren’t exactly cheap here in Australia. I’ve also got ISTA P and INPA available, just been relying on convenience of BimmerLink lately.

Thanks

[07lilredwagon]

Have you checked voltage output at the alternator when the car is running? It sounds like you have.

It should show with a multimeter 13.5 to 14.5 or so...

You mentioned that you just replaced the voltage regulator on the alternator but not the alternator, is that right?

Can you have the alternator load tested?...

Are all connections good?

All grounds good? Check for high resistance, corrosion, etc.

Jp