[MtBMW73]

I need the collective wisdom of this forum to help solve my IBS/battery issues.

A few days ago I posted that my battery was dying after less than a week of not driving. Since the pandemic, the car does not get driven all that much. (I no longer have a daily commute.) But even still, I would expect the battery to hold a charge for longer than a week.

I currently have the car at an independent mechanic for annual state inspection, and while it's there, I asked them to load test the battery or otherwise figure out if it has an excessive parasitic draw.

The shop manager just called and said they are going to charge up the battery and keep it overnight. He also mentioned they found IBS codes, which may have something to do with it, but he is not sure.

I've been getting these codes for a while:
38B4 BSD: No Message from intelligent battery sensor
38A4 Intelligent battery sensor (IBS): Communications fault

My 2013 E92 does not have an IBS. So I don't know why I am getting these codes. I clear them and they obviously come back.

I replaced the battery in November 2020. I registered the battery after replacing it, and now I am wondering if that is the cause of these codes? And could this be why my battery is potentially prematurely failing?

Has anyone solved the mystery of how to address the IBS codes on a BMW with no IBS? There are a lot of threads on this but no clear definitive answers (that I've been able to find).

Any help appreciated..

EDIT: I found this old post, made by me, when I was originally replacing my OEM battery back in November 2020. In that post, I stated I had gotten the 38A4 code before I had replaced the battery. So I guess that means it is not the result of me registering the battery. (Interestingly, I was also questioning why my car was missing the IBS cable.) But that does not explain why I am getting IBS codes in the first place...