This original BMW generator/starter is used on B46X, B58C, and B58D models equipped with the 48V mild hybrid configuration. This unit is used in place of a traditional alternator, allowing for power regeneration and smooth start/stop transition when driving in city traffic.
Applications include G42 M240i, G20 M440i, G22/G23/G26 M440i, G30 540i, G01 X3 M40i, G02 X4 M40i, G05 X5 40i, G06 X6 40i, and G07 X7 40i.
Only for models with 48-Volt Energy Recovery System.
This part is listed by BMW as BMW part number 12318490540 (12-31-8-490-540) and is described as Genuine BMW Starter/Generator (48V).
Supersedes the following obsolete BMW part numbers:
12318490440 (12-31-8-490-440)
12318490434 (12-31-8-490-434)
12319889141 (12-31-9-889-141)
12318699365 (12-31-8-699-365)
BMW Fitments:
2 Series
G42 / G43 (2022+) > M240i
G42 / G43 (2022+) > M240i xDrive
3 Series
G20 (2019+) > M340i
G20 (2019+) > M340i xDrive
G30 (2017-2023) > 540i (B58C 2020-2023)
G30 (2017-2023) > 540i xDrive (B58C 2020-2023)
G01 X3 (2018-2024) > X3 M40i B58D (2020-2024)
G02 X4 (2019-2024) > X4 M40i B58D (2020-2024)
X5 Series
G05 X5 (2019+) > X5 sDrive40i RWD B58C (2019-2023)
G05 X5 (2019+) > X5 xDrive40i B58C (2019-2023)
G06 X6 (2020+) > X6 sDrive 40i B58C (2020-2023)
G06 X6 (2020+) > X6 xDrive 40i B58C (2020-2023)
X7 Series
G07 X7 (2019+) > X7 xDrive40i B58C (2019-2022)