The switch LED is connected between terminals 2 and 3, with 3 being earth. So when the switch is turned on, terminal 2 then becomes live sending current to the fogs and also sending current through the LED to earth. The LED should be independent of whether fogs are connected or not.
Possibilities are:
Poor earth to terminal 3
LED has failed
Could it be working ok but, because of the position of the switch low down,, you cant see it as you are not looking directly at the end of the toggle (it may not be that bright)
If no joy, I would pop the switch back out and test it on the bench using a battery connected directly to terminals 2 and 3, but make sure 3 is -ve as LEDs are usually polarity sensitive.
I would also be wary of upgrading fuses unless I were sure of the rating of the wiring. Just because “it works” doesn’t mean it’s safe. It may well be ok, but just saying it’s not good engineering practice. Not sure you will find a 12 A fuse either.
That’s where the benefits of relays come in where the whole circuit can be wired and separately fused to suit the load.
Last edited by Deejay; 08/12/22 07:56 AM. Reason: added about fuses
