G12 740 2021 vmax remove

For a 2021 G12 the first thing that decides the whole job is which engine/DME you actually have:

• 740i / 740Li (B58TU) – normally Bosch MG1CS003
• 740d (B57) – Bosch MD1CP002
• 740Le / 745e – B58 + hybrid, limiter behaviour also involves the hybrid/EME strategy

Generally, on these MG1/MD1 units the top-speed limiter lives in the DME calibration (speed limitation curve plus the tyre/rim-dependent limit values), so it is a normal read → modify → write job — no coding in other modules. What is not trivial is access: MG1/MD1 are Tricore/Aurix with protected flash, so you need a tool that supports either OBD unlock/virtual-read or bench/boot mode (Kess3, Autotuner, CMDflash, Trasdata etc. depending on what you own). Checksums and the RSA-signed areas must be handled by the tool itself — hand-patching without proper checksum correction will brick the DME.

Practical order:

• Full read + two separate backups of the original before anything.
• Battery support on the car if you read/write via OBD.
• Modify only the vmax limiter section; leave the rest of the calibration untouched if the car is otherwise stock.
• Remember the physical reason for the limiter — if the car is on 250 km/h-rated tyres, removing it is a customer-liability topic.

To give you something more specific, post:

• exact variant (740i / 740Li / 740d / 740Le) and engine code
• DME hardware + software number from the ident read
• which tool you are using and whether OBD or bench
• whether you already have a successful full read, and if the car was tuned before

With the DME ID and a screenshot of the tool's ident/read screen it's much easier to say whether your tool can do it over OBD or whether the unit has to come out for bench.

ch89909
Can’t we remove the speed limiter using an FSC?

Short answer: yes, there is a way to enable Vmax with FSC on the MG1/MD1 side — this is not a flash/tuning operation, but a feature activation following factory logic. The forum's BMW MGD1 FSC Creator (Resource #632, support thread #2220) does exactly this: it reads the DME and generates an offline 188-byte FSC without a ENET/OBD session; "Vmax DME1 / DME2" are among the supported features. The generated file is then written to the DME with E-Sys.

But there are two important points:

• An FSC does not remove Vmax on every vehicle. An FSC activates a feature that is already present in the DME calibration. The Vmax FSC is mainly relevant on the M / Competition side (S58, S63). On a B58-based 740i, it must first be verified whether the DME recognizes this Application ID — if it does not, the FSC will not be accepted, or it may be accepted but the behavior will not change. In that case, the classic MG1CS003 read → vmax map → checksum → write remains.
• ch89909 looks suitable for the VIN-short field because it has 7 characters, but make sure it is the last 7 characters of the VIN.

To continue, could you provide the following:

• Exact variant and engine: 740i / 740Li (B58TU), 740d (B57), or 740Le?
• DME hardware + software number (ident readout)
• Is E-Sys installed, and can you read the vehicle's current FSC status (FSC status / Application ID list)?

Reading the FSC status is the fastest way: it shows which Application IDs the DME supports and gives you the answer before generating an FSC unnecessarily.

Note: the limiter is there for a physical reason — if the vehicle has tires rated at 250 km/h, removing it is a matter of customer responsibility.