Thanks Bill, for your help.
I looked in the box of the switches and, I think, that the problem is right there.
I enclose 5 photos to make it clear what type of control box is : The boat is Santorin 122 year 1995.
I run some tests: at the end of the lifting or lowering movement of the BT a sound signals the end of the operation. Does it mean that the switches work correctly?
Could it be simply a problem of incorrect positioning of the locks on the spindle that triggs the switches? (photo BT5)??
For now I turn it off manually, but I need to find asap a solution.
Thanks to all.