Advantages of daytime running lights

By Allen Penticoff

Damn! That was close. I was about to pull out onto Highway 251 from our frontage road, when out of the misty morning suddenly appeared a small black sedan. Over the 30 mph speed limit – as everyone else, always – and with no headlights on. I hit the brakes and held short of pulling out, but was about one second away from being broadsided.

She had every legal right to be driving without her lights on, but it was not a good idea, particularly on this morning with no sunshine. Black cars blend in with the blacktop of our roads making them especially hard to see, and the days of shiny chrome bumpers are long gone. Other vehicles approaching from the other direction had their headlights on and were easy to spot.

Admittedly, I had not turned on my headlights yet either. But the incident prompted me to do so. Just because you can see fine does not mean you can be SEEN. When did manufacturers stop building cars with automatic daytime running lights (DRL)? The answer is; it’s complicated.

My old 1981 Honda Civic has a manual light switch (and now a separate switch for the tail and dash lights) and no buzzer to warn they are on. My 1987 VW Vanagon Camper has a manual switch, but if you forget to turn them off it reverts to only running lights – sparing your battery some load. I’d long planned to install an electrical relay in the Honda making the lights automatic – engine is on, so are the lights, and likewise if engine is off, so are the lights. An old Fiat 128 SL I had used a very similar system. You could not leave the lights on accidentally – same is true of most motorcycles, which are required by law to have their lights on all the time for being SEEN.

The auto industry has for far too long hung onto this outdated notion of headlight switches that can be turned on without a key. I have never had a reason to turn on my headlights without having the key with me. This still persists in some low-end models. Most new vehicles have automatic headlights that come on when it gets dark, but have to be turned on manually to operate in other low light conditions. Our Volt has both automatic daytime running lights and automatic full headlights. If on manually and you turn the car off, you will be chided to turn off the headlights. Again, why would I have the headlights on more than a minute or two after getting out. My old Plymouth mini-van will turn off the lights after a few minutes if you forget.

During our vacation trip out west I drove with my headlights on all the time in our 2002 Suburban. Chevrolet had a joke of small daytime running lights on this vehicle, and like all others like it – seems to have one that is burnt out. I prefer to be seen, so I turn them on manually, and forget to turn them off half the time until I hear the reminder chime. Most drivers out west do not have their headlights on even though we are all traveling at 70 mph on two-lane highways.

I had thought daytime running lights had been mandatory, but after looking into the law, found that it has become optional – and apparently most manufacturers are opting not to include this as a standard feature. I am quite surprised the insurance industry has not demanded NHTSA (National Highway Traffic Safety Administration) require all vehicles to have this simple life saving feature. A 2008 study by the NHTSA however found that DRLs did not statistically influence safety. I find this very hard to believe. European countries, in particular dark Scandinavians ones, find the opposite – improvements in accident reduction by three fold. It was Canadian requirements that got General Motors to actually lobby to have DRLs be mandatory – since they did not want to have model variations. And so it is, that in the United States it is not federally mandated to have DRLs. Many states, like Illinois, do have laws requiring headlight or DRL usage any time the windshield wipers are in use though.

Europeans and their car makers have been far more accepting of DRLs. Recent technology improvements have brought us the dedicated LED type daytime running light that uses far less power (lower emissions) than a full on headlight, and reduces glare while still providing the benefit of increased visibility. Newer cars also have switching to turn off one headlight while a turn signal is in use – helping to see the turn signal light. Out on the highway – one can see that roughly half the cars have some sort of light on during daylight hours – and they are clearly easier to spot than those without lights on.

And so we have, in the United States, a variety of displays of DRLs as the individual manufacturers incorporate them, or not, into their vehicles. As an environmentalist I’m a bit torn between advocating headlight usage all the time which does enhance safety – and the environmental impact of doing so. So, I’ll fudge a bit and say, if it’s the least bit gloomy – turn on your lights. Bright sunny day – save the pollution and turn them off, but if you have newer low watt DRLs, do by all means use them all the time as the environmental impact is minimal.

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