Digging the web a bit more, there seems to be further information via
Transportation Canada.
Issue:
On certain vehicles, a problem in the high-voltage system could cause a short circuit. If this happens, there could be a loss of power to the wheels and/or the high-voltage battery could overheat.
Note: This problem would cause a warning message to display on the instrument panel. This recall only affects the 3-door model. This recall replaces Transport Canada recall no. 2024-253.
Safety Risk:
A loss of power to the wheels could increase the risk of a crash. A battery that overheats can create a fire risk, even while the vehicle is parked and turned off.
Corrective Actions:
To reduce the safety risk, BMW advises that you should park your vehicle outdoors and away from other vehicles or structures until the recall repairs have been completed. BMW will notify owners by mail and advise you to take your vehicle to a dealership to update the vehicle software.
This is consistent with NHTSA's language:
Description of the Defect : Faults may occur in the high voltage battery or high voltage system, which could be caused by various reasons. These faults may result in a short circuit.
FMVSS 1 : NR
FMVSS 2 : NR
Description of the Safety Risk : This may lead to an overheating of the high voltage battery and, in rare cases, a thermal event, even when the vehicle is not in operation.
Description of Remedy Program : Potentially affected vehicles will receive a software update. This software includes a diagnostic function which detects a malfunction in the high voltage battery (in the high voltage system) and subsequently discharges the battery (below 30% State-of-Charge (SOC), high voltage battery emergency mode). Owners will be notified by First Class mail advising them of the recall and to schedule an appointment with an authorized MINI dealer to have the remedy performed for free. If this condition were to occur to a potentially affected vehicle prior to this recall, the remedy would be covered by the
MINI New Vehicle Limited Warranty program. Therefore, reimbursement for a pre-notification remedy re Part 573.13 and Part 577.11 is not necessary.
How you going to know which vehicle have an issue and 12000 owners driving a LEMON is like Russian rulete ?