We have a Fresenius k machine that will not power on all the way. it seems to have enough power to light up the "power" led amd start the fan in the Power supply. after that the machine will not start the software, i don't even get as much as a beep. we have swiched out power supplys as a whole as well as function, power logic, actuator and power logic cables. any advice would be great.

Did you try swapping the card cage as a whole?

we swiched out all the boards including mother and distribution. by chance the blood pump came unpluged and that turned out to be the problem.