Originally Posted by HoddiesMog
All, My rear fog light refuses to work. No 12Vto the light. There is a good fuse and the the rear fog switch brightens as you would expect when you press it ( doesn't when you remove the fuse). Is there a relay for it somewhere and if so where? Or I'm down to tracing wires from the switch

As others have said it may well be the PCB board if a simple poor connection is not found. There is a rear fog light relay that provides conditional (headlights need to be on) power to fog light when selected. Unfortunately this hard wired micro relay is an integral part of the PCB. Have a look here for Rog's investigation into a "stuck on" rear fog light, noting that relay driver transistor required replacement. I appreciate your issue is the opposite but note that one headlamp mode or other needs to be selected.


Richard

2018 Roadster 3.7
1966 Land Rover S2a 88
2024 Royal Enfield Guerrilla 450
1945 Guzzi Airone