IDL40 2nd light flashing during start of cycle?

When I start the dishwasher on cycle 1, the 2nd light (wash) starts flashing in time with a loud clicking noise coming from inside the control panel. Normally it eventually it stops, and washes the dishes as normal. This time, the at the end of the cycle there was steaming hot water in the base of the dishwasher, hours after it should have finished, and the 2nd and 4th lights were flashing. I've looked at the thermostat inside the control panel and it's still in place, i can't find anything loose in there.

Any ideas? I do hope not a new dishwasher!

Thanks, Alison.