If you didn’t read part one you can find it here.
My first task was to see how easy it would be to remove the fridge worktop, turned out to be quite easy, some easily removed stick on covers were all that were hiding the screws.
Once inside I could confirm the Led light had been jumped over to the 12v connection for the fridge itself, as I suspected. And it was a case of removing those wires and putting in longer ones (of the correct colour no less) and a fuse holder for the 2a fuse specified in the manual.
So now that was done I could remove the two extra wires that had connected pins 9 & 10 together, now whatever power source I use, mains or gas, the interior light will work. And best of all the fridge will only work (when on battery), with the car running as it should have in the first place.
Next I removed the pin 9 wire from the connector and fitted a spade to it, I then cut the 12v loom after the psu and leisure battery and put spades on each end of that wire, and also added two wires to pin 10 and earth to activate the relay, only when the car is running, and fitted all the spades to the relay. When there is no power coming from the car, the leisure battery powers all the 12v systems (or the psu when on mains), when I connect the car and start it, the relay activates and disconnects the leisure battery from the caravan and connects it to pin 9 to charge on route.
Please note, I have electrical experience and have posted this for information purposes. Do not attempt to modify things unless you have the knowledge required to do so.
For wiring diagrams on the original set up, with leisure battery and the full modification click here