Haggis, as Rog suggests re-purposing the redundant air con switch is essentially not feasible. Concentrating on your aim of adding spot lights, once you have located the redundant blue/yellow wires under the o/s wheel arch, after removing wheel and scrapeing back underseal, you have the solution to spot lamp wiring on front of car. You will likely find two blue yellow wires terminating in a double female bullet connector sprouting from the loom. One runs back to dash area and the other provides loop across to n/s wheel arch terminating on a single female bullet connector to feed spot lamp for that side. As mentioned above the other end of blue/yellow wire provisioned to feed both lamps will be found behind the dash tucked out of the way. I've included the well illustrated post from Dave relating to how and where he found the cable behind dash in quote below.
Originally Posted by Montegue
What's this then?
Well I never
Let's pull it out a bit
Removing the insulating tape
Revealing the three wires we've been looking for, sure looks like the fog light switch loom to me
The sub loom is quite long, it reaches the steering column cowl to the right
And all the way to the passenger side on the left
Hmmm, what's this then?
Oh silly me, I've got a switch for my front fog lights already! Interestingly it's a momentary switch
And finally, Morgan has kindly provided the wiring for a useful second 12v power supply or USB charger socket
I'm going to call this evening’s casual investigations a blinding success
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone