Ariston LED diagnosis

Hello,
I have a Ariston LSI61 dishwasher that has stopped draining.
It fills ok and seems to cycle but does not drain.
It has the usual result of filling the base tray and giving the LHS LED indication that I saw elsewhere is this fault.
I can get the unit to cycle the LED by holding mains on and program selector button, it cycles in a binary fashion (i.e. more than 1 led at a time).
So…
1. How can I diagnose further.
2. What do these LED modes mean and can they help me?

Any thoughts or pointer to earlier thread covering this (sorry its late…) would be appreciated.

Regards