Why High beam DRL is a bad method to implement DRL

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Rand

Rand

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My2011 forester uses the high beams(h9) for DRL and runs them at lower voltage.. to lower the brightness.

This is a bad idea because you will eventually get a sooty buildup inside the bulbs from not being run hot enough.

Then when you actually need your high-beams they wont be as bright as they could have been.

Pic=1000words
This picture isn't perfect the orange is actually MUCH MORE Visible in real life ie: the photo doesn't look as bad as it actually is.

Whats missing from the photo is the fact that the sides are all partially coated just not Quite as bad as the tip
drivershighbeam-small.jpg


Compare the bottom right on the bulb-side (nearly clear) to the top-side, and left side of the bulb and you will start to see the discoloration.
 
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Oh and just for laughs I ran across this while I was looking for the best price on replacements

PIAA bulbs with really bad marketing

H9 Xtreme White Bulbs
Made with "Xtra" Technology
Provide A Brilliant Xtreme Cool White Light
Blue Top Coat Adds A Slight Blue Tint
65W=120W XTRA, 4000k Color


so now 65w is 120w, and coating them with a blue tint adds light??
spankme2.gif
Bad PIAA BAD
09.gif



Edit:Actually the high beams are 9005, not H9 whoops.. Musta been thinking too hard about the H9 in h11 mod.

Actually better they are much cheaper.
 
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Personally I feel Subaru and other companies know what they are doing. Who is to say that the coating you have would burn off after a few uses of the HIGH Beams?

How many people use their high beams on a regular basis anyway? In the last 5 years I can count how many times I have used my high beams on one hand.

Is this an issue? Or not? I have a feeling not.

Jeff
 
Originally Posted By: Jeffs2006EvoIX
how many people use their high beams on a regular basis anyway?

Depend on where you live. Around here there are very few street lights and most roads are darker than my ex wifes heart at night.
 
Originally Posted By: Trav
Originally Posted By: Jeffs2006EvoIX
how many people use their high beams on a regular basis anyway?

Depend on where you live. Around here there are very few street lights and most roads are darker than my ex wifes heart at night.


I use mine quite abit. Lots of deer out at night.

If there is no oncoming traffic (and im not behind someone obviously)

I'd heard running the high beams for 20m+ will reduce the coating but who can do that while driving.

A new PAIR of 2005's are around 12$.

Originally Posted By: NHGUY
Then dont buy a Subaru.Vote with your wallet.


You are joking? or trolling? either way that's nonsense.
 
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I've experienced the exact same thing with my subaru's high beam bulbs that also double as the drl's. I can't knock subaru for using the high beams as drl's though. Even with the build up in the bulb, it's still pretty darn bright. I can't think of a better bulb to use, knowing that it will have a shorter life since it also doubles as a drl. I wouldn't want my headlights to burn out faster than normal, or my turn signal bulbs.. Using the high beams just makes the most sense. The only thing that would be better is an independent drl bulb by itself, but I don't know how or where you would implement that.
 
Well lets just have the low beams be DRL's so your adding hours and contamination to the low beam side. Then, when they burn out, and your running your brights to get home some night, I'll flash my high beams at you to remind you that DRL on high beams is the way to go.... DRL's really need to be high beams to maximize the life on the low beams that are used the majority of the time. That's why most motorcycles use high beams during the day also.
 
Originally Posted By: beanoil
Well lets just have the low beams be DRL's so your adding hours and contamination to the low beam side. Then, when they burn out, and your running your brights to get home some night, I'll flash my high beams at you to remind you that DRL on high beams is the way to go.... DRL's really need to be high beams to maximize the life on the low beams that are used the majority of the time. That's why most motorcycles use high beams during the day also.

2005-2007 Volvo V70 (may be other models too) have low beam as DRL at full strength, it also illuminates instrument but not the side markers and back lights.

It's very confusing, when I start the engine the instrument light and low beam are on but other lights are off when the light switch is at position 0(off). This switch position is for daytime driving.

When I switch to position 1 instrument light and all other lights are on except low beam. This switch position is for parking at unlit area in short period.

Switch to position 2 instrument light and all other lights are on including low beam. This switch position is for nighttime driving.

At night when I start the engine the instrument and low beam are on, I forget that I need to switch to position 2 to have other lights on.

I like to bypass the whole DRL but it is not easy to do on the 2006 Volvo. My other older cars don't have DRL (and they don't have TPMS either, Thanks God).
 
There should be a law that instrument cluster can NOT be lighted unless the exteriors are on. Too many people drive in the evening/night without realizing their headlights are off. Even I have done for a minutes or so :-(
 
Originally Posted By: Vikas
There should be a law that instrument cluster can NOT be lighted unless the exteriors are on. Too many people drive in the evening/night without realizing their headlights are off. Even I have done for a minutes or so :-(


I agree 100%, I don't understand why automakers do that. In my car the cluster illuminates when you switch on the parking lights which I think is fine, at least there are some exterior lights on.
 
High beams are most commonly used for DRLs for many of the reasons given. But critically, it's because the high beams give the necessary beam pattern for a DRL. Low beams are not nearly as conspicuous at a glance to other drivers because of the relatively low and wide beam spread. In other words, they're not as effective as DRLs as high beams are. The high beam gets the light up into other drivers' eyes so your vehicle is better seen.

Don't take that above statement out of context, however. There are certainly POOR implementations of high beam DRLs as well. Most notably, I've found that late model Chryslers run the high beam DRLs at a pretty intense level, so intense that it's hard to make out that their full high beams AREN'T on, and it's just the DRLs. True, with an intensity that's reduced enough to get good DRL function without also blinding others, you do get the "brownout" syndrome on the bulb. Compromises.

The other option is a dedicated DRL lamp. Some automakers have done this. Notably, many GM trucks did this for a while and the Honda Ridgeline and Acura MDX also used to do this. They were not fog lamps lit up; they were dedicated DRLs. This, however, adds complexity to the system, cost, etc. More compromises.

I didn't find the "vote with your wallet" statement to be so out of place, at least not when taken in context. Automakers at least perceive that the vast majority of drivers don't care one way or the other (or even KNOW) that the high beams are used as DRLs. The more cars they sell like that, the more their perception is reinforced. Will Subaru get the picture that someone doesn't buy their car because of the DRL implementation? Probably not, but there are certainly avenues for communicating with them about it.
 
Stop using garbage bulbs. My BMW uses the high beams as DRLs and I use HIR bulbs and don't have a spec of discoloration after nearly 2 years.
 
In few more years, even the lowliest car will come with LED DRLs. Thanks but no thanks Audi :)
 
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Originally Posted By: simple_simon
Stop using garbage bulbs. My BMW uses the high beams as DRLs and I use HIR bulbs and don't have a spec of discoloration after nearly 2 years.


I've read cases of people having HIR bulbs shatter in DRL applications. I would chock it up to finger oil/residue on the bulbs, but people swear up and around that the bulbs were untouched. Do some searches. I am not EXACTLY buying it. I switched my HB DRL's to Fog DRL's.
 
Originally Posted By: Pablo
Originally Posted By: simple_simon
Stop using garbage bulbs. My BMW uses the high beams as DRLs and I use HIR bulbs and don't have a spec of discoloration after nearly 2 years.


I've read cases of people having HIR bulbs shatter in DRL applications. I would chock it up to finger oil/residue on the bulbs, but people swear up and around that the bulbs were untouched. Do some searches. I am not EXACTLY buying it. I switched my HB DRL's to Fog DRL's.


Again, two years and not a single burnt out bulb in my HIR highs (DRLs) or lows. I also run 14-15v to my lows so they're about 20% overdriven.
 
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