Extending headlight life

O, that's _YOU_ driving with dimmed headlights!! :)

Maybe opt for yet another option:

5 Don't drive at night because the rest of the planet likes to see where you are.

Seriously, Is blowing out a headlight such a huge problem, then? They aren't hard to replace and cost relatively little. I may have to replace a headlight once every couple of years or so -- Don't think it is much of a worry as opposed to driving safely and making sure you are being seen. Driving with dimmed lights can cause someone not to see you, since all other lights are fairly bright. Next time someone flashes highbeams, it is me. :) Remco

First of all, it is illegal in almost every state (if not everywhere) to drive with just the "parking" lights on. Also, it has been shown numerous times that DRLs do NOT cause early failure of the lamps. Stop thinking and drive.

My '97 predates DRLs but I drive with headlights on all the time since they go off with the ignition key. In 8 years, 120k miles I seem to recall replacing each side 2x, hardly excessive.

My 1995 Subaru doesn't have DRLs, but it does have ignition-switched lighting. When I think about it, on sunny days in the summer I'll turn them off, but most of the time I drive with all the lights on all the time. And in 4 years and over 60,000 miles, I've never replaced any bulbs except for both fog lights - which I found highly ironic, considering I only use them when I should - as in when there's fog. Even still, most auto bulbs are very inexpensive, and the headlights aren't much more. You have to think, is it worth your safety to run with excessively dim DRLs on at night?

Some years back, before the DRL craze was in full swing, there was another craze - people, mostly young people, putting these smoked plastic lens covers on their car headlights. (and tail lights) The instructions which came with them warned that they were for daytime use only, but still a large amount of idiots hit the road at night with those things on. I sometimes wonder how many kids died because of those damn things. I doubt that the DRLs are much brighter at night than those lens covered headlights, so I would recommend the use of your regular headlights and high beams as needed.

-Matt

Driving with DRLs and parking lights on at night is illegal in most juristictions. They are not intended to allow you to see where you are going but, as the name implies, for oncoming cars to see you in daylight. I once received a ticket in New Jersey for driving with my DRLs while it was raining; headlights were required by law whenever it was raining. The DRLs were not considered sufficient. Consequently, if you would be required to drive with headlights on if the car was not fitted with DRLs, I would turn the headlights on.

I live in Canada and my last three cars have had DRLs. None of them had the bulbs fail prematurely.

It's impossible to drive with both the DRLs and parking lights on, since as soon as you turn the parking lights on the DRLs will go off. The problem with driving with DRLs only is that aside from the reduced intensity only the headlights are on, the parking lights are off so you have no markers or taillights. From the rear the car will be completely dark.

JD wrote:

Maybe on your vehicle it's impossible; on my MY04 WRX it's 100% possible to drive with only DRLs and parking lights.

Duh...wrong...turn on your parking lights above your steering column and don't touch the light switch stalk.

Well...

Methinks if the cost of driving is THAT critical that a little extra headlight life is important to you, it's time to hang up your keys and get out the walking shoes. Talk about penny wise and pound foolish... what's the cost of that first ticket for driving without your headlights gonna cost in terms of headlamp bulbs? (:D right back at ya!)

Rick

There's still ANOTHER stupid idea from Subaru! Ask anyone who understands halogen lighting and they will tell you LOW VOLTAGE WILL CAUSE PREMATURE FAILURE of Halogen lights. It's pretty simple, Halogen lights that DON'T get to proper operating temperature WILL NOT "Recycle". If you don't understand how they work, read up on them and see why they fail with low voltage.Metal that boils off the filament is redeposited back on the filament due to the gas in the bulb.If it never gets to proper temp, it simply coats the glass. Way to go Subaru!!!! another dim bulb idea.

Rastis,

Every manufacturer that sells cars in Canada, including Ford, installs their DRLs the same way; reduced-brilliance halogen. Don't be so stupid.

If you don't believe me, read all about it from YOUR choice of Halogen Lamp manufactures. It's a fact...low operating temp (low voltage) dramatically shortens the lamp's life.

My 2004 WRX will (continue to) run the DRLs if you actuate the parking lights *with* the light switch stalk, moving to the first detent position (parking lite actuation). In fact, when I first got the car, I found myself cruising around at nite like that several times...with just DRL- level headlights on, thinking, "Gee, these headlights aren't as bright as I'd like!" ;-)

Interesting theory. Now let's see how well it fits observations.

My 1997 Legacy Outback, bought new in spring 1997 here in the Greater Vancouver, BC, Canada, region and with 269,000 hard km on it, has (like all Canadian cars) daytime running lights. Would you care to guess how many times I've replaced the headlights?

[Hint: One fewer than the number of times I've had the front brakes re-done, and the same number of times I've had the back brakes re-done, and the same number of times I've had the clutch re-done. Arithmetically challenged thieves with both hands and both feet amputated will have no trouble counting any of these numbers except the front brake replacement number.]

David

Here is a site that explains it all......

It explains exactly HOW they work, and why dimming them causes premature failure and darkening of the glass globe. In studies, the "Norn" has been that once the tungsten deposits itself on the glass it DOES NOT clean up and the lamp is on its way out. Over 10% too high will cause the temp to skyrocket, Over 10% too low will bring on failure too.

Apparently he really is that stupid. Your point JD about every manufacturer, including Ford, using the same reduced power DRL's went right over his pointy little head.

Here is the halogen info from that ceiling fan site that you provided: Dimming Halogen Lamps: Line voltage (120V) halogen bulbs can be dimmed by regular incandescent dimmers. Using a dimmer with halogen bulbs actually has negative effects. When dimmed, the halogen filaments do not reach the 250 C needed for the halogen cycle to take place. This could cause the inside wall of the bulb to blacken reducing light quantity and life. Running the lamp at full brightness will help restore and clean the bulb.

Then you go on to say...

Funny, that's not what I read above. Bulb deposits will return to the halogen cycle once proper operating temperature is reached.

But this whole point is not applicable anyway. It's the people who run their ceiling fan lamps down to 30 - 40% output over a long time that will experience blackening in halogen bulbs. DRLs in Subaru vehicles operate at approx. 80% output which maintains the heat necessary for the halogen cycle to work. What evidence do you have to the contrary?

I'm sick and tired of you spewing crap on this NG. Go away and find something constructive to do with your life. Maybe you will even find the time to defend yourself against the Prodigy investigators who are now alerted to your constant abuse of this newsgroup.

Headlight bulbs are not expensive. Do the rest of your town a favor and just leave the lights on.

P T wrote: