ok guys ..im new to the forum and need some help with my machine

until about a year ago this was working fine until a resistor on the board decided to burn out ..i got a couple of second hand boards off ebay in the hope that i could get it going again but so far ...nothing..

at the moment the power supply is lighting up all its led's so the fuses are good
the led's of the payout tube board are all lighting up and the led's that show on the reels are also working ...the green 12v led on the main board is also alight .but nothing else is working .no lights no display no initilisation of the reels or anything else at all ..

i have checked over the harness's and all seem fine ..

can anybody help to diagnose what may be the problem ?? or does anybody have a spare board or new machine i could buy that i wont have to mess with this is such a wicked machine and i dont really want to scrap it ..

many thanks in advance

john