Negative switch problem, slightly different from normal.

mlines wrote:

What Jimny ( model/ year) do you have? 

I have to ask why the original one is not sufficient? 

So What jimny and year model and market is this? 
Doesn't all have the rear fog light?

does vary if it is down in the rear bumper lamps or up in the main rear lamp assembly between markets and year, but they all have them here in Norway.

I can't see your diagram, you can attach an image into a reply on here, but they come out small.

Anyway, if you have a 3 terminal switch with a telltale bulb, look at what I sketched, the tell tale bulb connects internally to one switch blade which goes to the load, and there is an odd terminal for the other end of the bulb (different colour or size) which either goes to earth (positive switching) or live (negative switching)

If the tell tale bulb is on all the time the circuit is "live"  it sounds like you have the switch blades wired backwards, swap the feed and load terminals over.


(normally the switch is put in the wiring to the relay coil like I did it, then you wire a fused live directly to the lamps through the relay contacts, but for a 21W bulb it makes no difference where the switch is)


Oh, and you are only allowed to use the rear fog in conditions of reduced visibility, when you are required to have either dipped headlights or front fogs on (or both if you really want...) so wiring it off a headlight or front fog feed is correct.