I have a fiat 500 - I sometimes leave my headlights on when I switch engine off and next time I switch engine and headlights on I get a general warning triangle on the dispaly and a message "check number plate lights". How do I get rid of this? Surely I don't have to take it to the my fiat dealer every time for a re-set! The first time I did this I did take it to the dealer but at that time I didn't know what was causing this to happen - they check it out and said they couldn't find a fault.