Whirlpool ADP4601 Fault Help

I acquired a 2 year old Whirlpool ADP4601 Dishwasher which wasn’t working.

On pressing the start button the drain pump would run for a second or two but then I would get 6 flashes of the LED located by the start button.

I replaced the inlet water valve solenoid but still kept getting the 6 flashes. I took the control panel off and on looking at the PCB there is obvious overheating damage to the board itself and some of the chips.

I have managed to get a second hand working board with identical part number, software etc.

I have fitted the new board and as soon as I press the power button the start LED is flashing in groups of two. Looking on here that would seem to indicate a water leak and that the float switch has tripped. Now I have stripped the machine down and cannot find a float switch anywhere!

If I hold and press the start button for a few seconds, on releasing the button, the drain pump will work and will empty any water in the sump but the light is still flashing. I have manually filled the machine with a jug and the drain pump clears it all. Unfortunately no water is coming in via the inlet valve.

Can someone confirm my machine has a float trip and where it may be ?

If it doesn’t what else could 2 flashes mean?

Lastly as the PCB is second hand could the 2 flashes be stored from the previous machine? If so how can I preform a reset to clear the code. The dishwasher has a selector knob, start button and power button.

I have tried to put the machine into the diagnostic mode following advice from the forum but it won’t go into it.

Thanks in advance for any help and suggestions.