I want to unlock the Mercedes Benz factory top speed limit which is 250km/h. Which program can I use to unlock it? and how to remove the speed limit set from the factory? is that possible with a Chinese C4 and Xentry that is not connected to Mercedes?
Here’s the clue.
MB Star DAS/XENRTY: can increase but not remove speed limit if with Development Mode
DTS Monaco: Yes
You could do them offline using Vediamo or Monaco but from an experience you better of with MB SD Connect C4 or VCI multiplexers to used those software. Meanwhile, you will need special CBf/Vsb/smr file or seed-key calculated to get the required access to the ecu and cpc. Some people can help you with that calculation. Unfortunately, we don’t.
In a word, you will need Vediamo/DTS together with the correct files (vsb w cbf) or regular file with seed key (bought) to gain access for coding.
MB SD C4/C5
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.
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):
The better solution is Vediamo or DTS Monaco.
How to change/disable speed limit (Vmax) on Mercedes with Vediamo?
Example on MED40 engine.
In Vediamo software, select V Ecoute
Upload a CBF file that you have saved on desktop
Got the engine module on your car
For example on this car it is MED40, (unlock me97 will not need calculator )
Right-click ECU and go to Properties
Select ECU – manual command input
We send the command 27 0B
open Seed Calculator
We write 4 bytes and get the code to send
Press Generate to generate a key
Copy and paste 4 bytes of the key and paste to vediamo
27 0C write code
Send command again
Access is open
Go to Variant coding
From the factory the car has a limit of 200 km/h
We change the speed limiter to 250km/h, press ECU coding.
Coding success. VMAX (Factory Speed Limiter) was changed.
If it is ME97 engine, the procedure is easier, does not require seed calculator.
Select ME97 engine
Click sub-options to select “Function”
Double click “DJ_Zugriffsberechtigung”
It will show access permission
select “Coding” option from menu,and then“Variant Coding”
Now select “Vmax”,and then select new max speed from right list
How to Remove Mercedes Speed Limit by DTS Monaco?
Example on ME97 ECU
1.You need t unlock ECU DiagJob–>Zugriffsberechtigung 1 and Zugriffsberechtigung 2
(click to enlage images)
2.Choose Domane “Implizite Kodierung ME97”
3.Choose desired value for Vmax