Dimplomat / Limona HJA 8552 won't start?

Hi - we have a washing machine purchased from howdens around 7 years ago - model number HJA 8552 (which i gather is a either a Dimplomat or Limona brand).

We turn the machine on and select a normal 40 degree wash, at this point the 'Stop' LED is blinking every second. If I press the start button, I can then hear water running through the detergent drawer. Water runs for around 5 seconds, then all activity stops. The Start LED remains lit, as does the door lock LED, and nothing is flashing.

It has, on a couple of occasions, filled the bottom of the drum with a couple of inches of water, and selecting the 'drain' program has drained the water away.

The Spin function works fine.

I have removed the back cover and located a sensor with 2 wires in the rear of the drum - I assume this may be a temperature sensor. I have removed it and cleaned the muck off it, but it made no difference.

Does anyone have any ideas what to try next?

Many thanks in advance.

Mike.