I have just finished putting a new plug on my caravan only to find the fog light did not work. after checking my plug again I noticed that the one on the van didn't work. I have checked the fuses, all good so I would guess the switch for it must be switching a relay.
Reading a thread from last year it would seem it is located in the engine compartment. However as there is no ticking from a relay to give it away I do not know which one it would be.
Can anyone help please?

Hi

What build and engine do you have ?

I assume that we are discussing REAR foglights.

On my 2006 x2444, the rear foglight circuit does not include a discrete relay, as the wiring conects directly to the "switch control unit" which is buried in the dash, forward of the auxiliary switch bank.

Operation of the rear foglights requires ignition ON supply via fuse F37, headlights ON, and the rear foglight button pressed.