Faulty display on w211

Hello. My CDI 220 of year model 2002 has shown on cluster this error message " faulty display". At the same time the following functions work no longer:
Power seat. ( Despite the seat-heating still works)
Rear headrests
Gas gauge at bottom
Key Fob central locking/ unlocking ( including Trunk and petrol door lock)
Rear shade roll .
It is good to mention that early this month I have two times experienced unlocking problems that keyfob didn't respond but could manage and it went ok later until this message came up suddenly with all the symptoms mentioned.
It happened the day after a ride on a rainy day. I have googled since weeks on different forums which almost all confirmed that I have a bad SAM. Have detected the one in the trunk but it looked like brand new and never wanted to go further unless I am 100% sure that it caused it all. The only contact that I came to on my car was that I changed the Automatic transmission plug adapter because there was a oil leak through which I also unplugged the battery cables to deactivate the alarm while jacking the car. I would be very grateful if you confirm whether what I did was relevant or irrelevant. And what should I do to fix the issue.
Thanks in advance