I just bought a secondhand hyundai i30 1.4 crdi and found a strange problem. Fog lights won't turn on. I tried all the combinations on the switch, checked the fuses, bulbs look ok... The led DRLs around the front fog lights work normaly. Any ideas?

I'm fairly certain I'll never do it but if I ever changed my mind, how difficult would it be to add fog lights to my '14 GLS? The knockouts appear to be present but I know nothing of available wiring or how much work it would be to get a switch on the stalk.