Indesit di620: light 2 flashing?

We can't get our Indesit di620 dishwasher to work: light no.2 is flashing as if the normal wash cycle has just finished, but we can't reset it even by keeping the 'P' button pressed down for 5 seconds as per instructions. There is also a small puddle of water remaining in the filter 'well'. This is all very frustrating as I managed to get the door catch working earlier in the week using the suggested fix on your site, this worked a treat and dishwasher worked OK afterwards for one or two washes. Any suggestions please?