Strange happenings with 405 rear fog light switch

[505sussex]

Just got another 405, its a n/a diesel 1995 . When you put the headlamps on the rear fog switch LED comes on, even when switch is out, but no rear fogs come on. Nothing happens when you push the switch.

However, with headlamps off, (sidelight setting) when you push the fog switch, the headlamps come on !

As if there is a short between the headlamp circuit and rear fog, and someone has disconnected the rear fogs as a bodge.

Any ideas ?

[505sussex]

Update: Found out what was wrong, theres an earth connector inside the tailgate, and the connections were corroded. Cleaned, fixed all the faults at once.