What's the Deal with Headlights on/Taillights off?

I drive a lot. And thought I was noticing lately that people don’t put their headlights on when it’s foggy, raining, or just plain getting dark out. Sometimes, when you go to pass, you discover the headlights ARE on! But the taillights are not.

Who’s the idiot who made the decision to make cars that have headlights on and taillights off? Didn’t they ever consider the fact that maybe people coming up behind someone in limited visibility could benefit from being able to see the person in front of them?

Did they think it would be a money saving option? After all, those bulbs going out once in the lifetime of a car could really kill someone’s wallet. :rolleyes:

I just don’t get it.

Those are likely DRLs (Daytime Running Lights? Lamps?), which are always on when the car is running, rain or shine. The drivers are still supposed to turn their lights on like normal when it’s dark or the weather is inclement.

I really don’t think anyone is doing that on purpose. All cars have special taillight bulbs that come on when the headlights are on.

The problem is, just like any other bulb, they can burn out and they are especially hard for the driver to know about. Drivers can’t really see if those are functioning are not and there is no good way to know in most cars unless the driver does a manual inspection or someone tells them.

The helpful thing to do is to let drivers know that at a red light or any other time you can. It could save them a ticket or even an accident. People have told me my brake lights were out and it was appreciated.

I’m pretty sure this is on purpose, and it really annoys me too. If it’s raining, snowing, or if you’re driving in to the sun, taillights make keeping track of the car in front way easier. I always make sure to turn mine on in such conditions.

I see the same lights light up when the person hits the brakes, and these cars aren’t way old or in bad shape, so colour me :confused: as to why their cars work this way.

I can’t rule out that there are cars out there that function like this. However, it is different bulbs and some can go out and not others. In the taillight assembly there are bulbs for brake lights, hazzard lights, headlight indicators, reverse lights and maybe others.

Any of them can go out independent of the others and the car doesn’t have to be old either. Because the bulbs are the same type, they often go out about the same time on both sides.

My car has those Daylight-running-lights that are on whenever driving.

Sometimes, around sundown when it’s just turning dark, I have arrived home, shut the car off and went to turn the lights off, only to discover I had never turned them on at all. The DRL was enough for me to see in the evening light. But I expect my taillights were not on for other cars to see.

So it can easily happen accidentally.

True. Bulbs burn out. But unless there’s some epidemic around here that causes them to go for no reason, there’s just too many cars out around here with this problem for me to think that’s the root cause.

I’ve stopped many times to tell people about different things, depending on the situation, so I’m in complete agreement on assisting.

I’m inclinded, now, to agree with the suggestion that these are the automatic headlights that come on when you start the vehicle. If this is true, however, I’d be seriously wondering why they didn’t design the taillight to come on as well. If you can be seen better with your lights on, it should apply to both directions!

What-- do you think that people are intentionally disabling them?

I’m pretty sure you are seeing Daying Running Lights, which on many (not all) cars do not activate the taillights. It may be because in situations where visibility is helped by the headlights the taillights won’t help as much. Either way, the DRLs didn’t activate the taillights in my Saturn or my Subaru.

Daytime Running Lights are mandatory in Canada. Therefore, due to economy of scale, they are also included in cars destined for the United States even though they are not mandatory here.

From Wikipedia:

No. I don’t. I’m also not convinced these people know their taillights aren’t on just because their headlights are.

I guess I’m just not making myself clear here, although I thought I was. I’m saying that the car companies that are making the headlights come on automatically should also be making the taillights come on automatically, too. If the purpose of having them is so others can see you, it makes sense to have both the front and back lights on.

Dammit! This isn’t a thread about boobies!

Some do. Mine come on automatically when it gets dark enough (it has a light detector).

Other than that, there’s no need to have the taillights come on. The reason for DRLs is apparently a consideration for pedestrians, who generally don’t have to worry about a car backing up on them at high speeds.

DRL have been shown to significantly increase safety on 2-lane highways, even in broad daylight.

Cite. It’s actually a page of cites, but it’ll do.

I’d have to disagree with this. Apparently these people don’t know that even though their lights are on, their taillights aren’t. That means they don’t activate their taillights when the conditions require them, like in fog and such.

I wasn’t even aware that it was possible to manually turn on the headlights without the taillights coming on too. How do you not turn on the taillights? (Not talking about DRL).

I apologize, because I’m likely dense and not understanding you, but I’ve never seen a car that required taillights to be turned on separately - you turn on the headlights and the taillights go on at the same time. I’m sure there may be cars out there where this is the case, but I’ve never seen one, so I can’t imagine they’re so prevalent in an area that it’s the cause of a noticeable problem. My experience has been that if a car has front lights on, and taillights not on, the front lights are DRL and not full headlights.

Not just for pedestrians. DRL makes a car substantially more visible to oncoming traffic, which reduces head-on collisions on two-lane roads and country roads where cars have to move over to give each other room to pass.

Boggette: I’m not sure what you’re arguing. What you are seeing are daytime running lights. The taillamps don’t go on because A) they provide little to no benefit in daytime lighting conditions), and B) it’s possible that if the taillights are on in daytime conditions, it will be harder to see the brightness variation between normal taillamps and brake lights.

The one potential drawback of daytime running lights is that they tend to delay the time at which people turn on their regular headlight/taillights. So here in Canada around dawn, dusk, or very dark and cloudy days you see lots of headlights and fewer taillights.

In California a law recently went into effect requiring headlights to be on whenever windshield wipers are on. I would guess that they are already required for fog. This law specifically says that DRLs are not adequate - headlights (and thus taillights) are required.

Now if the bozos who don’t turn on their headlights would only get the word.

Let me make myself perfectly clear…

If ANY type of front lights (includes DRL, ‘regular’ headlights, fog lamps, running lights, etc.) are on, the taillights should ALSO be on.

I don’t know how to say it any clearer than that.