A: Instead of sounding the horn in a built-up area between 11.30 pm and 7.00 am
B: On a motorway or unrestricted dual carriageway, to warn of a hazard ahead
C: On rural routes, after a sign warning of animals
D: On the approach to toucan crossings, where cyclists are waiting to cross
View hint
When there’s queuing traffic ahead and you have to slow down or even stop, briefly showing your hazard warning lights will help alert the traffic behind to the hazard.