A quick update, thanks again to everyone whose responded.
I have checked that the cigarette socket is live when the ignition is off: I can confirm the socket is live, I have a 12 volt light that plugs into cig socket and that worked.
Fuse in the plug is intact, I couldn’t read what it was rated at though but the details on Amazon say it is fitted with a 10amp fuse - so presume that it is.
I think the wiring is the right way round, as the charger shows all being well for a few seconds then the error light comes on. I would think a wiring issue would be binary- it would work or it wouldn’t.
Ivor Mog - you make a very good point, I can’t argue your logic!
So tomorrow CTEK 5.0 will be procured...
Thanks again for all the pointers.
