Explantion: Drivers are not permitted to sound the horn in a built-up area between 11:30 pm and 7:00 am unless there is a traffic emergency. Only sound the horn to warn other road users of oncoming danger or if they need to be made aware of your presence for safety reasons. Sounding the horn does not give the driver an automatic right of way. Never sound the horn to provoke a reaction from or to rebuke another motorist.