Just been out and followed what Richard said.
When clicking the "faults" (the one that looks like a box rather than a button) nothing seemed to happen. No window animation to confirm it had been pressed.
I tried reading the faults again and this time it managed to go through the sequence without losing connection. No faults were returned and the boxes above, F8, F9, FA, FB, FC have a 0 in each of them. (not sure what f8, f9, fa, fb and fc are for)
Disconnected and that's that til the morning when igo on the school run and we'll see what happens.
Incidentally, there's a guy in the next village from me, selling a block and compressor for £60. Says he got it in a box of spares and doesn't know if it's working or not. Worth a punt????????