620i voltage regulator question
2008 620i not charging the battery.
Engine runs as long as a charged battery is connected.
Engine dies if the battery is disconnected while unit is running, (I assume it should continue to run).
Output from stator is about 32 volts AC across all combinations of the 3 outputs. I think those are good numbers.
Voltage across battery stays about 12v when unit is running, does not go up to 14v as i would expect.
When regulator output harness is unplugged, the output from regulator is about 4.5v DC (red to black).
Does this sound like a bad regulator? Just wondering about what i should expect as an output when measuring unplugged (the 4.5v number). Would a regulator fail in this way?
In my limited electronics understanding, I theorize that only 1 of the 3 phases from the stator is making it out of the regulator and two of them are not; since, if all 3 were making it out then it would add to 14.5 or so? (3 x 4.5)...or am I showing my lack of understanding? So there are two bad rectifiers inside the voltage regulator(?)