Many newer cars have ECUs that are "locked", which means a standard plug-in tool cannot read or write the software. Alientech, the maker of the KESS3 tool, has released update 3.62, which adds a way to work on the locked Bosch ECU in recent BMW M and Alpina models with the S58 engine. Here is a plain-English summary of what is now possible and what it means if you own one.
BMW M and Alpina with the S58 engine (update 3.62)
This update covers the Bosch MG1CS049 ECU used with the S58 3.0 twin-turbo petrol engine, on models from 2021. The ECU has to be unlocked on the bench once. After that, Alientech says it can be read and written through the diagnostic (OBD) port, so later visits do not need the ECU removing again.
Models listed by Alientech:
- BMW M2, M2 CS, M3, M3 CS, M3 Competition, M4, M4 CS, M4 CSL, M4 Competition, X3 M and X4 M
- Alpina B3 and B4
What this means for you
If you own one of the BMW M or Alpina models above from 2021 or later and were told it could not be remapped because the ECU is locked, it is worth asking again. A few practical points:
- Support depends on the exact ECU and software version, so we check your registration and engine before confirming anything.
- The first job involves a one-off bench unlock with the ECU removed, which takes longer than a plug-in remap. After that, Alientech says later work can be done through the diagnostic port. We will tell you what is involved before booking.
- We still scan the vehicle first. We want the battery, sensors and fault history to be healthy before any calibration is written.
- We keep a copy of your original software so the vehicle can be put back to standard.
Being able to read an ECU does not mean every vehicle is a good candidate, so we will give you an honest view once we know the car and how you use it.
Check your vehicle
Send us your registration, model and engine and we will check whether your car is covered and what the work would involve. We are a mobile service based in Denton (M34 3FJ), covering a 30-mile radius.