I came across a helpful post on a forum that might shed some light on the issues you’re facing.
Problem:
I am having an issue with coding and flashing ME9.7 AMG modules. I have tried many combinations of hardware and software. First I will describe the problem, and then the steps I have taken to attempt to fix it. I try to perform a coding (or flashing) operation, with Vediamo 4.02.02 or Vediamo 5, and I get this error:
Error: Service execution failed. Reason: CEASAR: DiagManager: 06067: DiagService refused.
This would indicate that the ECU is not unlocked. I have tried the various DJ_Zugriffsberechtigung selections, getting the Result: 0 response that we are looking for. I have tried this with four different ECU modules. Two regular ME97AMG (2MB) and two 66MHz ME97AMG (4MB) modules. I have a tried direct connection to the ECU on the bench, and in vehicles (via the ZGW, etc). Always the same results.
Moving over to DAS (both through Xentry and DAS Standalone) results in “Communication Error” dialog boxes, which also indicate a locked ECU. Monaco gives NRC=22, NRC=44 or NRC=88, depending on which unlock commands had been issued ahead of time.
I have also tried this on three different laptops, with software running natively and in VMs. No differences. Always the same error.
As for connection hardware, I have now tried C4, Openport Tactrix and SM2Pro. Again, all give the same ‘Refused’ error.
Lastly, a very knowledgeable person logged in to my machine, and tried it, and he also had the same result.
This leads me to believe that there is:
1. Likely not a hardware or PC issue, as so many combinations give the same exact result
2. Not necessarily a software issue as Monaco, Xentry, DAS and Vediamo all fail
3. Not likely an ECU hardware or firmware issue, as I have four different ones (that all run the engines to the cars they go to)
4. Some procedure I am missing or doing wrong
All other functions seem to work just fine. I can interect with the modules. Virginize them via VVDI, and then teach in drive authorization. Read actual values, do adaptation resets, camshaft teach in, etc. Just cannot flash or code these.
I have read many times that ME97 is a “seedless” ECU. Seed Key options are in the menus, but I have been unable to get any of that to work. Surely someone else out there has encountered this, and knows what to do? Please help!
Solution
Figured out the problem! If you are building a bench programming rig, most guides will tell you that you need one of the grounds, +12V going to pins 15 and 16, and CAN-C bus. In addition to this, you need to activate Terminal 87 power at pins 3 and 5. Suddenly, everything will work! What makes this odd is that I had problems in the car coding, as well. It appears I have additional troubleshooting to do there, too.
I retested with VM’s running both Vediamo 4 and 5, with Star C4 and SM2Pro, and this checks out. I also tested with an early (2007) ME.97AMG ECU and a later 66MHz version I was able to code both ECU’s with both sets of software and J2534 hardware.
Source: https://autogmt.com/threads/mercedes-me9-7-amg-scn-coding-problems.1099/#post-5942