Fisher & Paykel 601 is now dead!

Machine is 17 years old – Smart Drive 601
Have replaced the main board a couple of times over the years.

Yesterday found it beeping on the spin cycle but had not finished the rinse even though the water was drained out. Only way to clear it was to turn it off for a couple of minutes. Turned it back on, set it to rinse and the issue appeared again a couple of minutes. Repeated the procedure and it worked all right.

Today, the missus said the display board was turning on and off like it was possessed, flashing until finally the machine just wouldn’t turn on.

Now If I leave it off for 5 minutes, when I turn it on either:
– the display flashes a few lights and beeps a couple of times then goes out. Pressing the power button does nothing
or
– the display lights up as usual along with the normal power on beeps but still cant be manually turned on.

I’ve visually checked the following:
Out of balance switch – appears OK
Display board – appears OK
Main board – appears OK including the fuse which I used a meter to test.
Pump – no leaks, spins freely and unplugged the connections to test if machine will switch on
bottom of washing maching (inside cabinet) – no water
No water leakes in the main CB area
Lid switch is ok visually with the board apart – & tried to manually hold in
water solinoids OK
Wires down the side of machine appear to be OK

My thoughts are the main board is buggered???
Both boards are blue in color.

Any assistance would be greatly appreciated.