Diagnostic code P1AA900 (Battery Management System subsystem): anyone else?

[Sunshine Daydream]

My new GV60 standard (~2600 miles on the odometer) recently threw code P1AA900 with a "possible condition with your Battery Management System has been detected" warning. Have scheduled a service appointment, though not nearly soon enough: limited appointment availability at my dealer.

A few days prior a dialog box popped up on the infotainment screen stating "Update was unsuccessful. Please try again when restarting the vehicle later." There was more info on an initial screen, but it disappeared before I could digest it. It was unclear what this update was about, and I did not see another notice the next few times I started the car. Forgot about it; the message reappeared a few days after the battery warning (and, again, an initial screen with more info disappeared before I could snap a photo).

Last Weds evening used an EA charger without incident (from ~30% to 80%), ran a few errands, then plugged in on my home Level 2 to get battery state to 100% ahead of a roadtrip. I unplugged at ~10 pm, about 10 mins after reaching 100%, and went to bed.

Woke up the next morning to find app notifications and emails from Connected Services every 15 mins or so beginning at 12:58am: Your GV60 has a battery issue. Charging is limited to 80%. Schedule a service appointment.

I've charged a few times at EA since the message first appeared, and there has been no change to the code. Driving and (L3) charging seems otherwise normal.

My internet searches have not identified any reference to this code with a Genesis, but I see service bulletins for Kia and Hyundai EVs referencing this code and possibly indicating "cell voltage movement" or "abnormal cell voltage change after charging".

More ominously, a Kia Kona electric service bulletin of October 2023 (link) suggests that code P1AA900 is an indication for replacement of the Battery System Assembly (BSA).

My prior EV was a Chevy Bolt, so I'm no stranger to battery issues and remain chill for now. But disappointing.

 

[Sunshine Daydream]

UPDATE

I see another owner reported the same "Check Electric Vehicle Charging system" warning (post 12 in Another VCMS Software Update (Campaign 910G)), so this may be one to watch.

at my service visit this week, the dealer retrieved the diagnostic code from the buffer but said the system was not currently sending the code. The relevant battery system was within spec.

They applied the fix for the new VCMS software update (campaign 910G), the 80% charge limit was removed, whole thing took 2 hours.

I've since used a Level 3 to 80%, and topped up to 100% on my home level 2. No issues so far. I did not document my home charging rate prior to the update but the most recent home session ran at 9.0 kW.

FYI, I now think my reported "update was unsuccessful" warning is a red herring, something related to an update of the Genesis app. The update was seemingly applied one morning over bluetooth, before I had a chance to connect the usb cable.