Ikea Whirlpool Dishwasher. A weird fault?

A Model AWF415s

I went out to the above today. Customer reported that it was flashing 2 flashes.
Looked at my chart, understood it as water leakage fault.
Removed the front plate (as you do), and it was full of water which had lifted the fload and put it into flood protection mode.
I looked at the late type Askol circulation pump by the rubber couple that tends to perrish, it looked as though it may have sprung a leak from there.
I drained the base off and wrapped the pcb up in a dry towell so I could run the machine for a few secconds to test for a motor leak.
When that machine filled up with water it was pulsing.
It would fill for 2 secconds, stop for a seccond, then fill for 2 secconds then stop again.
It repeated this process untiil it overfilled slightly allowing water to run down the breather tubes (hence the base been full) then the motor kicked in. The customer told me that it had been doing this weird filling thing for a while.
As luck would have it, I had a new pressure switch in my car, so I fitted it, and started again. Still the same.
My thoughts are: perhaps the pcb had got wet at some point maybe? or could it be anything to do with the flow meter on the L/H side of the machine?
Once the machine was running, the circulation pump was coughing and spluttering like these Askol ones do so it does need a motor, but I dont want to fit one knowing there is another fault.
I have litraly done hundreds of these in the past. but this is a new fault on me..
Help please..
Thanks
Robert.