Why don’t taillights turn on with daytime running lights?

Share

Why don't taillights turn on with daytime running lights? Nearly every night, I see cars with only their front daytime lights on and, unless you're close, they're completely invisible from behind. I've nearly run into someone because I couldn't see them. I guess they don't realize their lights are off because their dash lights are all on. I've done it myself when I'm driving an unfamiliar car – when I see the lights on the dash, I assume the lights are on. And sometimes it's hard to tell without getting out and checking. – Sandesh, Richmond, B.C.

You're not the only driver who's been scared out of their living daylights by a nearly invisible car.

"A backlit gauge cluster can easily create the illusion that all lighting is operating," says George Iny, president of the Automobile Protection Asssociation. "Consumers complain to us every year that, particularly at dusk and just after sunset, drivers appear to be unaware that their taillights are off."

So why don't taillights just stay on all the time? Canada made automatic daytime running lights – either headlights, yellow turn signal lamps or a dedicated light – mandatory on new vehicles built after Dec. 1, 1989. Studies had shown that front lights reduced collisions because they made oncoming vehicles more easily seen – from as far as a kilometre away – by drivers, pedestrians and cyclists.

But those studies also found that daytime rear and side lights did not make a significant cut to the number of crashes, Iny says. Mainly because they're not bright enough to be seen from a distance during the day.

Even if the those daytime taillights were brighter, cars travelling at normal speeds can see vehicles in front of them in plenty of time – from about 150 metres away – to avoid a rear end collision during the day, says Transport Canada.

Back when the rules were made in 1989, speedometers and other gauges weren't backlit all the time. They came on with the headlights and were a good (and often the only) indicator that lights were on. That changed with the popularity of backlit gauges.

Plus, if drivers aren't familiar with the light controls (say, in a borrowed car or a rental), they may think they've turned on the headlights but actually they just have the running lights on.

Headlights that turn on at dusk have been around for years, but they add cost – and they can be set so they don't come on automatically, Iny says. Scandinavian countries require headlights to be on all the time.

A spokesman for one Canadian auto maker, who asked not to be attributed, said even if they wanted to, Canadian auto makers can't introduce fixes – like always-on rear taillights – on their own because they have to follow whatever Ottawa mandates. And because the U.S. doesn't require daytime running lights, there's no push from down south to fix the problem.

Transport Canada says it's working with auto makers, importers and other countries to draft an amendment to the lighting regulations, says spokesman Maryse Durette. A draft is expected to be ready by early next year.

Here are some of the possible requirements they're considering to prevent drivers from unwittingly driving dark:

• Headlights and taillights that turn on automatically at dusk.
• Dashboards and gauges that stay dark during the day.
• Taillights that come on when daytime running lights are on.
• A dashboard warning light or sound that signals when headlights are off at night.

Durette says observations of traffic show that most drivers are turning their lights on at dusk. Still, Transport Canada recommends that people check their owner's manuals to make sure they understand the headlight settings.

If you have any driving queries for Jason, send him a message at globedrive@globeandmail.com or contact him through Twitter: @JasonTchir

Update: If you commented that Canadian auto makers are indeed free to exceed the regulations, you were correct. They're allowed to build cars with taillights that stay lit during the day, Transport Canada says.