How to Change Vmax in Mercedes ME 9.7?

 Question:

I finally ordered and received a MB SD C4 DoIP Multiplexer from China (through obdii365.com) and after over a 2 weeks, I managed to connect my SL to a Xentry version from 2019.
So far so good, and it took quite a while to get to that point with multiple installations, iterations and errors/problems etc..

What about the speed limiter? I saw a video on Youtube and it looked pretty easy to alter the Vmax from 250km/h to 280km/h. Again, is that possible with a Chinese C4 and Xentry that is not connected to Mercedes?

Answer:

You can change individual settings under "adaptations". You can do firmware loading or SCN (i.e. VIN encryption) coding without a live/licensed version of MB Star. But there are many things you can do in the adaptations under "Development Data". For example, you can set VMAX there to increase (but not remove) the speed limiter.

The Chinese clone MB SD C4 is capable of doing firmware/SCN coding, but because you don’t have a valid login for MBZ’s online servers, you can’t do that. There are many modules in the car that don’t need firmware or SCN code installed. For example, let’s say you blow a SAM. You can replace it with a new or used one, then Star diagnostic system can set the “adaptations” specific to your car. Also, with Developer Mode enabled (via the license key), you can change most of the adaptations that are contained within the firmware. Vmax is one of them.

The good news is that most Chinese clone SDS system have “developer mode” enabled. This is something licensed shops do not have. It’s meant only for part developers. With this, you can access almost all the adaptations that get set with SCN coding, but with the need to be “live”. the Vmax setting in the ECU is a development mode adaptation.

Check if Developer Mode is enabled on your software, if yes, you can increase speed limit but NOT remove it.

Here’s how to change Vmax in ME 9.7 (ECU used by M272/M263 engines):