SMEG DWI612C not heating water

My SMEG DWI612C dishwasher is not heating the water, it goes through the wash cycle, but beeps every 2 mins or so and the wash cycle never completes. If you stop the cycle the water is cold. If you put in hot water manually cycle does complete.

I’ve replaced the heating element assuming that was broken, but has had no effect. Have also done the reset trick shown in this forum.

Starting to suspect it’s the PCB which is probably not worth replacing on a 6 year old dishwasher, so before I replace it has anyone come across this problem before(couldn’t see anything similiar in the forums)