PLEASE HELP! Zanussi ZDV12002FA Cutting-Out

Zanussi Dishwasher
Model: ZDV12002FA
PCN: 91107900603

Hi all,

I’m in need of some help please…..

My Zanussi ZDV12002FA (slimline) dishwasher is cutting-out during the warm-wash cycle. The issue was first noticed about two weeks ago where after a supposed completed wash, the dishwasher was opened and water was sitting in the basin. The dishwasher is 7 years old. I initially thought it may have been a drain pump issue/water intake v/v.

Following a long investigation and stripping everything down, I eventually found a ‘relay’ type noise emanating from the main PCB. It occurs during the warm wash cycle only as follows – the ‘clicks’ occur, the dishwasher cuts-out + power-off, shuts down the pump motor – – relay noise again – power will come back on and pump motor will start back up momentarily to resume cycle – – relay noise again and cut-off and so on. It will do this for a few minutes and then just seem to give up (machine completely cut-out).
With the dishwasher cut-off from own accord, I’ll leave standing for 10 mins and then I’ll be able to power on with the interface ‘on button’ and then the dishwasher will complete cycle, but sometimes I think it repeats some cycles – not 100{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d}.
The user interface/wash selection lights will also come on and off in line with machine powering up and then off with the PCB noise.

The PCB is located at the rear of the machine at the bottom.

Things I have checked/changed:

– Checked continuity on drain pump = all ok
– Checked all lines and hoses = all ok
– Checked continuity on door latch switch = all ok
– Replaced water inlet v/v with new as I originally misdiagnosed the clicking from the PCB for the water inlet v/v solenoid = all ok
– Replaced pump capacitor as I mistook the pump starting/stopping for a dodgy capacitor = all ok
– Checked continuity on water heater = all ok
– Replaced circulation pump with new as I thought this may be on its way out and perhaps short in motor windings causing the cut-out = new part and motor all ok (old motor was fine as cut-out still occurs)
– Mains voltage to machine throughout is good @ 240V so no issue there
– Checked continuity on float switch = all ok
– Cleaned up all basin door seals + filters
– Checked for blockages throughout the entire system = all ok

I disassembled the PCB from the machine, but saw nothing obvious. Difficult to inspect as it’s a closed unit.

I’m not sure what to do now, but I’m thinking the next thing to check would be the thermostat. I think this is integrated into the turbidity sensor. As said before, the heater works fine and hot water is present during the cycle + continuity of heater within measurements.
Perhaps a dodgy thermostat is causing too much heat to come from the heater motor and PCB is cutting the power-off as a result. Would explain the ‘cool-off’ period when everything will work fine again after 10 minutes??

Failing this, it must be the PCB. The only other thing to check would the pressure/overfilling sensor.

Please help!

Thank you so much in advance.

Ps. I have videos of the issue – could I post?