[mariomakiii]

Hi everyone,

lately I'm having two error codes, reported using BimmerLink. The car is an F10 (2010) 523i N53
One is:
- 12 Motor electronics
---- 210901 (0x210901 Generator, communication, no communication)

Other one is:
- 30 Electric steering lock
---- D52C44 (Signal error (energy generation status, ID: ST_ENERG_GEN) Sender: DME1 - Invalid)

Car runs fine, I've checked the voltage while running (in the menu), varies from 13.3V (does not oscillate, lowest I've seen was 13.3 but it's usually stable around 14.1V) to 14.9V while regen braking kicks in. The battery wasn't discharged and seems to be charging fine so far. Also, no issues with the steering.

Weird thing is, if I clear the codes, sometimes they both come back immediately, sometimes the first one comes up without the second one and sometimes second one comes without the first one...I've checked other posts, everyone is pointing to the alternator. So far, I've checked only the voltage and the wire coming to the alternator for comm, looks fine for now.

Could both of them be related to alternator, should I start by checking the diode, or does anyone have a clue from where should I start investigating?

Thanks & cheers!

[edwarj3]

Hi - I am also getting this recurring error code and wondered iof it is the alternator as I think it has become a little noisy.... did you resolve this with your car?

[mariomakiii]

Originally Posted by edwarj3

Hi - I am also getting this recurring error code and wondered iof it is the alternator as I think it has become a little noisy.... did you resolve this with your car?

I'll copy paste from my other post:

Managed to fix it. As I was sure it was something around the alternator only and not other BSD consumers, I didn't give up. After doing some readings with oscilloscope, I was sure that the line was ok, measured the resistance from DME to alternator and it was also fine.
So, after two failed (new) alternators, I finally ordered one from BMW. They did notify my that the part number that I was looking to buy was replaced (not the one I found on realoem).

Cost: 1300€ and I'll get 470€ back if I send them my old one back.

Finally installed the third alternator from BMW and everything works fine, no more alternator missing codes, no more 210901 or D52C44, car always gets 14+ volts, efficient dynamics now always works (before it would register to blue on dash but the voltage would not kick up to 14.7V or 14.9V, now it does).
I would even say that the car runs much better, not sure how to explain it but I know "how it breathes" and now it just feels like the idle is more stable, acceleration feels better, not sure if it's just in my head but something definitely feels different (and good different).

For everyone who's in a similar situation:
- 1st alternator was Hella (caused the whole BSD line to go down, including water pump)
- 2nd was AS-PL (still had alternator missing codes)
- 3rd is BMW original (perfect!)

The new one from BMW is same like the old one, also Denso, but I've tried searching for the part number from the new alternator I received and couldn't find it in any other shop online (top secret lol)...

Weirdly enough, when I took apart my old Denso alternator, the regulator inside is from AS-PL (brushes had plenty of meat left, I'm guessing that just the regulator failed)...If that one worked for years, I'm not sure why the whole new alternator from AS-PL did not work...If I had more time I would probably just try buying a new regulator and try replacing just that part, but as the alternator is over 10 years old and I'm tired of this and I have to cover a lot of miles in the next two months...no, just no, it works, costs a lot but at least it's over now.