Fisher & Paykel dishdrawer?

Hi I have a replacement machine which I bought as the bottom board had blown due to getting wet. I have tried to put the drawers into my casing as my machine does not have the water softener parts so thought it would be better how ever even though the plugs and pipes all fitted when I tried either drawer in the bottom of my machine the top drawer flashed F1 and the bottom one remained dead unless I connected the heater out of mine and the rest connected to the replacement drawer which then flashed 99 in the display I would like to put the 2 better drawers into my cabinet the numbers on the control module are all 525 so in my reckoning they should all work how can I make them work any ideas?