[rogersmj]

I have been hunting a battery drain problem for a couple months, and the more data I gather the more confused I am.

Before someone tells me to search, yes, I have read quite a few "battery drain" threads on here. Many of them resolve to the cluster being the problem; however, in at least two of those threads, there were error codes specifically pointing to an issue with the cluster; I do not have those codes. I do have some error codes (attached), so I'm hoping someone can help interpret these to provide a clue that will help me get to an answer quicker/easier than I might otherwise.

Car is bone stock except for an Andream CarPlay unit that I installed 3+ years ago. Have never had any electronics issues until the last couple months, aside from occasionally iDrive would not shut off when I opened the door to exit the car -- this would happen maybe once every other month.

First noticed a battery issue on Dec 23, 2022 when it was -10F in the midwest; the car started complaining about a low battery charge and I should drive it more, and starting the car was sluggish. Car was on original battery at the time (about 50k miles/7 years old), so this did not shock me. It soldiered on, often indicating the battery was low (or discharging while stopped), which like I said I didn't surprise me since it was such an old battery.

Eventually I replace the battery in early/mid Feb 2023, with new AGM battery from AutoZone and code the battery myself with BimmerLink (eventually...that's a different story). Old battery was a 90aH, new one is 95aH, but I left it at 90aH because 95 wasn't an option when coding (and some material online suggested this was OK)...I only mention this in case it's relevant.

Since then, while the starting problems have gone away, the car has still been complaining about "Battery discharging while stopped" nearly every time I start it. The car is aggressively shutting stuff off to "protect" itself, and I mean aggressively...sometimes it will shut off the interior lights within seconds after I open the door. When I go up to the car after letting it sit for just a few minutes, Comfort Access does not work. If I put it in Accessory mode, it will shut off iDrive after a minute or two. Or it will just say "no" to Accessory mode and shut itself off entirely after less than 30 seconds. It never fails to start, however...but if the car thinks the battery is draining, then it could be overcharging/damaging the new battery so I really want to find this.

I pulled the Error Memory and Info Memory today with BimmerLink and got the attached. Can anyone glean any clues from this? I'm not sure what might be significant and what might be a red herring (or an effect, rather than the cause). For instance, do any of those errors indicate the problem could lie in the Comfort Access system, or are those codes there because the CA system is being shut off to conserve power?

From reading other threads, these are some culprits that others have had:
* Instrument cluster
* Water pump
* Comfort access door handle
* Some computer/ECM