[I]"My column Marshal Acton 2 , is dead . Power suplyy is it ok ... 18 V , but not light and not power on.
In board off buttons dont have 3,3 V - see picture​"[/I]

Hi I have the exact same problem, thank you for this post! 😁
I want to test stuff on the board connected to all the buttons but I can't get it out. There's 2 plastic hinges but even though I lift these the board seems stuck (no screws).
How did you release the board from the panel/chassi?[I]"My column Marshal Acton 2 , is dead . Power suplyy is it ok ... 18 V , but not light and not power