Car sign language: What flashing high beams and other signals mean
Open Road and the NRMA are big proponents of the ‘thank you wave’. It’s an almost zero-effort way to acknowledge another driver’s courtesy or apologise for a driving error. In larger cities, especially, it’s a great way to defuse frustration that could otherwise lead to road rage.
But the courtesy wave is only one signal motorists share to communicate with one another. If you’ve been driving for more than a year or two, you’ve likely encountered ‘car sign language’ – a flash of high beams, hazard lights activated for a couple of seconds, a left-right-left cadence of indicators that has nothing to do with their regular purpose.
These signals are often a variation on the thank you wave – a way to express appreciation or some sort of information. Here’s a guide to what each one means:
A flash of high beams
This is the most common ‘car sign language’ signal. If someone flashes their headlights or high beams at you, the intended message will depend on the situation.
In a stationary or low-speed situation, such as a carpark or busy intersection, it usually means, “I see you and I’m letting you go first.”
If you’re in motion and a car coming in the other direction flashes its high beams, it’s usually a warning that a speed camera or the police are ahead. While there is no specific Road Rule in NSW stating you are not allowed to dip your lights to warn other road users, be aware, you could receive an infringement notice for it if a police officer alleges that while you were warning another driver, you also dazzled them.
If you’ve just cut someone off during a lane change, flashing high beams is slightly less aggressive way than a blaring horn to express displeasure (which can result in an on-the-spot fine!).
In the case of large trucks, if one truck overtakes another, the driver who has just been overtaken will flash his high beams to indicate the truck ahead is clear and can return to the left lane safely.
There is a host of other reasons someone might flash their high beams – you’ve forgotten to turn on your headlights after exiting a brightly lit area at night (or conversely your high beams are on and you’re dazzling oncoming drivers), there’s something wrong with your vehicle you’re not aware of, or you’re obstructing traffic in the overtaking lane. The legalities of using high beams for anything other than their intended purpose are covered here.
Hazard flash
If you slow to create room for someone to change lanes in front of you, it’s reasonably common to see a hand raised in thanks. Some people instead opt to switch on their hazard lights for a few seconds to express their gratitude to the motorist behind.
If a car in motion ahead of you puts on its hazard lights, the driver may be warning of a traffic incident or other obstacle that will cause them to slow down rapidly. Some modern cars have this built in – the hazard lights will go on automatically under sudden braking from high speed.
Flash of indicator
On two-lane country roads, sometimes a truck or other slow vehicle will give a flash of its indicator to tell the vehicle behind it is safe to overtake. This is incredibly dangerous, of course, as any driver can make a judgment error and being involved in a high-speed head-on collision will likely be fatal. Last year, the Australian Trucking Association urged its members to discontinue the practice. If you do get stuck behind a slow truck, wait for an overtaking lane or ensure you have clear vision and an unquestionably safe gap ahead.
Double flash of brake lights
If the driver ahead of you double taps the brake pedal, it could mean you are tailgating and he or she is not happy about it. Which driver has the moral high ground is irrelevant – this is a dangerous situation for all and could lead to a collision and/or road rage incident.
