What happened to your D3/D4 today?
As per previous post and against all advice I have changed my 12S and 12N sockets for a European 13 pin socket and changed the van to match.
In doing this I noticed that pin 2 on the 12N socket gets power on the rear fog light switching on, it is not the reserving light signal. That signal is from pin 1 on the 12S socket.
In moving everything now to a 13 pin socket my fog light on the caravan works correctly as does the reversing light when I engage reverse gear.
This means anyone that hooks up a trailer or caravan with a standard 12N+12S socket that is not modified to match the Australian 7 pin standard may find you need to switch on your rear fog light to make the reversing light on the trailer/van switch on and off.
I’m sure you all knew that already [emoji3]
Ron