Daytime running lights: what are they and why do you need them?
Which came first, the chicken or the egg? We may never know the answer to this question, but there are others to discuss, such as whether you really need daytime running lights (DRLs). We’re a bit more confident with the DRL question than the chicken or the egg question, so we’ll take a look.
Some governments believe that DRLs prevent accidents and have mandated their use on motor vehicles. These are mostly governments huddled together in northern climes, wishing the sun would come up. For example, Sweden, Finland, Norway and Canada imposed DRLs decades ago. However, the European Union also required them on most new motor vehicles by 2012.
So far, the United States government has refused to champion the cause of DRLs, citing a lack of meaningful studies indicating that DRLs reduce accidents or save lives. Defining DRLs is much simpler than explaining why you need them. So, let’s start there.
What are daytime running lights?
Despite government inaction, most new passenger cars, SUVs, and light trucks sold in the United States have DRLs. You may also hear them referred to as “signature fires”. These low-powered white lights automatically activate when you turn on the vehicle’s ignition. Often located around headlights, DRLs are found on the front fascia near the sides of the vehicle.
DRLs are the baby bear of front lights. That is, they are neither too bright nor too dark. They are perfect for illuminating the front of a car, somewhere between parking lights and low beams.
What are daytime running lights used for?
The purpose of DRLs is not to illuminate the view in front of your car. Instead, they make your car more visible to drivers and pedestrians as you approach. As a result, they point forward rather than down like headlights and fog lights do.
DRLs work best when ambient sunlight is low – dusk, twilight, cloudy days, etc. This is why Scandinavian countries, with notoriously short days, were eager to mandate them.
An unintended benefit (at least for automakers) of DRLs is that they are another avenue for branding. This is where the term “signature headlights” comes in. Audi pioneered the creation of a distinctive DRL pattern for most of its lineup. Additionally, DRLs make your car or truck look more technical and expensive.
How do you use daytime running lights?
There’s not much of a learning curve needed here. The DRLs work on their own. They come on when you turn on the ignition and go out when the headlights come on. The driver has no real control over the operation of the DRLs as there is no DRL on-off switch.
Under limited conditions, such as when parked with the engine running, your vehicle may provide a method to turn off the DRLs. However, the procedures vary from model to model.
Can you add DRLs to a car?
Yes, you can add DRLs to your vehicle if it does not have any. We do not recommend doing the job yourself unless you are an experienced DIYer. While installing a universal DRL system isn’t brain surgery and can be done in an afternoon, it’s your car’s electrical system, after all. Any misstep can have a negative ripple effect on the entire electrical system. In addition, the installation must follow specific regulations for the location and direction of DRLs, either by you or by a professional installer.
If you choose to get the job done, there are dozens of aftermarket DRL kits to consider. We suggest a universal kit adaptable to almost any car, truck or SUV.
How much does a DRL kit cost?
Do-it-yourself DRL kits are available online and at some physical retailers. Expect to pay $50 to $200 for a universal kit.
How much to professionally install DRLs?
Here is the bad news. Beyond the local dealership of your vehicle brand, you may need to do some legwork to find a competent professional installer for your DRL kit. That’s not to say they aren’t there, but many auto shops just don’t have experience with installation.
Your research efforts can pay off. Look for custom auto shops that specialize in exterior lighting. Expect to pay around $750 in many parts of the country. This rough cost estimate would cover a $150 universal daytime running light kit and three or four hours of labor for the automatic customizer.
The good the bad and the ugly
We will now move on to the question of why (or if) you need DRLs. It seems intuitive that lighting on the front of a vehicle helps pedestrians and other drivers see it. However, studies measuring their effectiveness during the day are mixed. As noted above, the US government does not feel obligated to make them mandatory.
What are the disadvantages ?
- Driver confusion – The most common complaint about DRLs is that they put out enough light to fool some drivers into thinking their headlights are on when they are not. Although approaching drivers will still see you, and you will see them, DRLs do little to light the road. Also, if your headlights aren’t on, neither are your taillights, which creates a major safety hazard in the dark.
- Additional fuel consumption – Believe it or not, DRLs add to the load on the alternator, requiring more fuel to be burned to meet power demands. It also means a little more stress on the alternator. However, the extra gas and added stress on the alternator is minimal and hardly worth discussing. Additionally, most DRLs in new cars today are LEDs, requiring very little power. Heated seats and heated steering wheels also sap alternator power, which requires burning extra fuel.
- They distract from other things – Most motorcyclists drive their vehicle with the headlight on, regardless of the time of day. They do this with the belief that it makes them more visible to other traffic. Many of these same motorcyclists claim that the proliferation of DRLs draws attention away from motorcycle headlights, reducing their safety. Some anti-DRL proponents argue that all DRLs draw too much attention from other drivers, making them less likely to notice pedestrians, cyclists, and other objects on the road.
What are the advantages ?
Statistical proof – Despite the government’s position that there is not enough evidence to justify imposing mandatory DRLs, there is some evidence. A 2010 publication from the Minnesota Department of Transportation stated that DRLs reduced daytime crashes by 5% to 10%. A 2008 National Highway Traffic Safety Administration (NHTSA) study placed the crash reduction with DRLs at 5.7% for light trucks and vans.
Dim ambient light – When there is enough light that you don’t need headlights, but the light is fading, DRLs are at least somewhat effective. They can increase the likelihood of seeing an approaching vehicle, especially a dark-colored vehicle.
Insurance discounts – Some insurance companies may offer discounts to drivers of vehicles using DRLs. These discounts may vary by state.
They look cool – There is no doubt about it: the current crop of DRLs adds a sparkle to the face of cars, trucks and SUVs by making vehicles more technologically advanced.
What is the future of daytime running lights?
There is no reason to think that DRLs are going anywhere, whether the government changes its mind and makes them mandatory or not. Automakers are always looking for economies of scale. In other words, lowering the price of a feature by installing it in more vehicles. DRLs are already relatively cheap, even on the secondary market. It makes sense that automakers would continue to fit them as standard on the cars they sell in the United States to help keep prices low in markets requiring DRLs.
We agree that DRLs probably help reduce crashes in low-light situations, such as on cloudy days or at dusk. However, we’re not sure it’s worth fitting an aftermarket kit to your 10-year-old mixer that doesn’t have one. On the other hand, we do not see any real disadvantage to having them, even if they do not provide additional security. Mandated or not, they are here to stay for the foreseeable future.