Hitzbleck:
The VMS of the car is sending more data. But i only need this payload at the moment.
I alreay read a lot about serial protocols but i'm still don't get it. Please give me a start or a hint where to search.
I don't know what it is that you want help with. You seem to know how to interpret the data.
If the problem is that you don't know how to receive the message then have a look at the third example in Serial Input Basics
It's not actually written to do what you need because it expects an end-marker as well as a start-marker. But it should not be too difficult to modify the code to get the number of bytes from the byte that follows the start marker and then count the next N bytes until the full message is received - rather than waiting for an end-marker.
...R