Dave, are you trying to wire the front fogs to the same circuit as the rear and use the same switch?
If you are something to consider…. The pcb that controls the fog lights with its dodgy relays is a just tad flakey. There are numerous reports of the fog lights (pcb) failing and mine have too. One day the fog lights decided to come on and stay on no matter what I did. So to enable the car to pass the MOT I’ve wired my fog to a temporary switch with a separate new circuit that is only live when the lights are on.
Long term my plan is to abandon the pcb but keep the same dash switches and have a more conventional control box under the bonnet, but that's when I have more time….
Rog, it seems that Classics and certainly +4 and Roadster have had provision for independant front fog light wiring and switching since at least 2006. It doesn't make sense therefore to put extra load on the rear fog circuit given as you mention, the fragility of control circuitry on PCB models, although since around 2014 they have used sealed BCU control.
I think the need for front and rear fogs differ slightly as well depending on conditions. Certainly our F54 Mini has independant controls for such.
Having looked at one of the PCB variants it would be an onerous task to re-engineer it exactly. Going back to basic relays and such kept out of the way of leaks is the way to go. Downside, the final result would be much bulkier but a fun project.
