Belfast Telegraph

Home Cars

What exactly are LED Daytime Running Lights - and what use are they?

By Paul Connolly

So, you’re in the market for a new or nearly new car.

You’ve read up on all the literature and the options, but one thing keeps bugging you: the continual mention of “LED daytime running lights”.

New car websites boast that the model has this thing as standard; with older models its sometimes offered as an optional extra.

Or, maybe you’re not in the market for a new or nearly new-ish cars. But you have noticed how many cars coming in your direction have their lights on?

Welcome to the world of LED Daytime Running Lights - the LED bit, by the way, stands for Light-Emitting Diode.

The answer to the conundrums above lies in the endless drive by governments and companies to make cars safer.

One key way to do this is to make cars more visible to pedestrians and oncoming drivers.

For some years now, it has been a legal requirement to have bright yet lower-powered lights constantly running on the front of a car.

Volvo has been doing this for years, and it’s now been adopted by mainstream governments in the EU and beyond.

They are usually integrated into the headlight clusters of the front of a car. They are not connected to the dip/full beam function, though.

This is because they are normally brighter than dipped lights and so cannot be used at night or they’ll dazzle oncoming drivers.

You don’t get them at the back of the car for the same obvious reason – they might blind drivers behind you.

The reason they are a legal requirement is that research shows they tend to work.

The EU and the UK Department of Transport found that Daytime Running Lights (DLRs) can reduce casualties because all road users can see a car sooner than without them. This obviously gives all concerned more time to react, thus saving lives.


The UK Department for Transport is on the record as saying: "Research has shown that DRLs are likely to reduce multiple vehicle daytime accidents and fatalities by up to 6% once all vehicles are equipped."

DLRs became law in the UK in 2011, with heavy goods vehicles being made to fit them the following year.

The key thing is that DLRs operate automatically in normal light conditions, but that headlights – dipped or full beam as appropriate – are required in low light conditions.

Research shows that DLRs have a fractional increase in fuel economy on cars, but that this is over-ridden by the saving to life, limb and damage.

Lighting tips for safe driving

Road safety and breakdown organisation GEM Motoring Assist has issued advice to warn motorists against bad lighting practice.

The advice comes as numerous GEM members have reported spotting vehicles with dangerous lighting defects.

1. Headlights out

There are huge numbers of vehicles with defective headlights on our roads, causing a significant risk to themselves and others on dark days and wintry nights, says GEM.

Drivers of these so-called ‘one-eyed monsters’ are on the road with only 50 per cent of the light they should have, causing other road users to easily mistake them for a motorbike. Parking and slow speed manoeuvring are also made more risky, as the absence of light means impacts with parked vehicles, walls, posts and trees are more likely.


2. Daytime running lights

Too many drivers are making themselves harder to spot from behind when daytime visibility is reduced, because they’re relying on automatic lighting systems and front-only daytime running lights.

The result is that visibility ahead could be reduced, and there may be no rear lights showing at all. GEM also reminds drivers of these vehicles that daytime running lights are fairly dim, and do little to illuminate the road ahead.

3. No lights

Drivers who consider that lights are for use only in darkness are causing danger to themselves and others. Once again, far too many drivers are making journeys on gloomy winter days without switching their lights on. Using dipped headlights for all journeys at this time of year is the safe option, according to GEM.

4. Obscured lights

Dirt, ice, snow and frost reduce the effectiveness of your car’s lights. It’s also an offence to drive with obscured lights. GEM encourages all drivers to ensure they make a careful check of lights before a journey, to ensure they’re free from dirt and ice, and to ensure they’re working properly.

5. Do the checks

Make regular checks of your main beams, indicators, sidelights, fog lights and brake lights.

6. Know your fog lights

Make sure that you actually know where your fog light controls are located, so you can turn them on and off as conditions require.

GEM road safety officer Neil Worth said: “Look after your vehicle’s lights and you have a much greater chance to see and be seen. It’s as simple as that.

“Don’t delay switching on your lights, get defective bulbs replaced as soon as possible and keep your lights clean. You’ll be helping to keep yourself and other drivers safe all through this winter.”

Familiarise yourself with any automatic lighting systems on your car, but don’t rely on them to provide the right level of visibility at all times and in all conditions.

Mr Worth added: “Daytime running lights alone are not sufficient to make you properly visible to oncoming traffic and other road users, especially in foggy or wet conditions. What’s more, you may be displaying no rear lighting at all.”

Belfast Telegraph Digital


From Belfast Telegraph