Here's what I tried
Diagnostic error code 3001 - cooler input error - folks on here thankfully we're able to translate as power failure on the input to fridge
Checked fuses all okay
Checked connections under fridge - by removing the circular panel on bottom left cupboard - it reveals fridge workings - at first nothing changed
Then pursued a failure of one of the cooler electronic parts - even contacted "penguin refrigeration" - very good company in Havant who offered to repair
On the day I took photos of fridge workings to send to Penguin I rechecked the connections nothing appeared lose but there was some micro movement - played around with connectors weirdly that seems to have fixed it
The connections are hard to reach and maybe not obviously loose but check throughly - I failed to do that first time round
There's still and error on the outside temperature control but at least fridge is working
Hope that helps
Thanks for taking the trouble to reply.
I had done a search and there are numerous problems/solutions recorded on here. The easiest thing to try was to turn the control unit off and on again (reboot) using the 1/0 button on the panel itself so I tried this first. Miraculously problem solved.
The fresh water tank was showing two thirds full on the panel at the time but was actually completely empty. We had been out for the day and I'd tried to put the fridge on just to keep the milk fresh then later found the water tank empty when trying to make a coffee. Perhaps I should have put 2 and 2 together and immediately blamed the control panel.
Anyway panic over, I don't need a new fridge and thanks again for you reply.