Pennsylvania Vehicle Lighting Codes

John_Galt

John_Galt

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...are quite poor to read through, if you expect to find answers.

I was interested in trying to find the maximum legal mounting height for fog lamps under PA law... and it appears that 42" vertically, 20" horizontally to the center of the lamps is the limitation. From being bounced back and forth between PA title 75 ss 4303 and various parts of Title 67, it appears that I could legally mount a set of fog lamps at the same height as both my headlamps and auxiliary driving lights. Besides practical mounting limitations, is there any reason not to maximize the mounting height of fog lamps?

PA Title 75 ss 4303
Relating to the promulgation of standards. Mentions fog lamps in "4303 g (3)" stating they may be used when a vehicle equipped with snow plow lamps, has them to be used when appropriate, in lieu (I guess, from the unclear wording) of the snow plow lamps, as long as they are aimed "correctly."

PA 67 ss175.146
Vehicle Lighting and Electrical Systems.
"(b) Lighting standards. Lamps shall comply with the vehicle lighting equipment requirements of Tables II, IV and V; Chapter 153; and 75 Pa.C.S. § 4301."

PA 67 ss 153.5
Contains the tables referenced by 175.146. No mention of fogs in the tables.

(Edited to add)
PA 67 subchapter E ss175.66
Relates to passenger cars and light trucks. So this is the section I am concerned with although the language of most of the other sections is similar.

Perhaps, though, this does in fact limit the color of fog lamps to white light.
" (g) Condition and position of lamps. Lamps shall be properly fastened; direct light properly; be of a color not contrary to Tables II—IV; and not be so obstructed by a screen, bar, auxiliary equipment or a device as to obscure, change the color of or obstruct beam."

However the tables do not reference fog lamps at all, so they have white, red and amber as legal colors for headlights/reverse lights, brake lights and turn signals. So perhaps *any* color goes for fogs. Going to find some RGB bluetooth controllable lamps to use (kidding).

(/Edit)
There are more sections under PA 67 175, but the wording is all pretty much identical. Nothing about height ranges for fogs, terrible aiming advice for both fogs and auxiliary driving lights ("beam must not be above the centerline of the lamp at 25'," which I would take to mean they mistakenly left out "[the center/hotspot of the] beam..." so as to account for maximum inclination of both a fog and a driving light, otherwise they're saying to point your driving lights at the ground in front of the vehicle...).

But per the letter of the law and the inspection code, it appears that a person could by all means mount and drive around with a set of fog lamps at the same center-of-the-lamp-height as their headlights, with the lamps pointed 0* downward, as long as the lamps are in fact fog lamps and are 20" (by center of the lamps) apart from one another. There is no specification for color for fog lamps that I can find, there is a requirement for white light from headlamps (but no reference to what that means, although a CIE chart is referenced to specify the legal range of "school bus yellow"), so selective yellow lamps should be legal as long as they're not also cornering lamps (per revisions to SAE J583, which is incorporated by reference under CFR49 [forget which ss] for commercial vehicles). I am tempted to do this and see how many state and local police I can argue with on the side of the road. Such a high mounting position, combined with such poor aiming requirements, makes a good case for trying to find a pair of Hella XLs or order a set of bosch compact 100 Fogs to use as auxiliary low beams. Legal in the Commonwealth, but perhaps too glaring for oncoming drivers in practice (though given the state of the average persons headlamps, aim, high beam useage, lightbar abuse etc it probably wouldn't stand out).
 
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jaycee88

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Besides practical mounting limitations, is there any reason not to maximize the mounting height of fog lamps?

Yes, since the purpose of fog lamps is to illuminate the road surface in fog, they should be mounted as low as possible so the light can better reach the road surface instead of being reflected back into your eyes. If you want to blind yourself, you already have your low beams, high beams, and aux lamps for that.

I am tempted to do this and see how many state and local police I can argue with on the side of the road.

What could possibly go wrong?
 
John_Galt

John_Galt

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"Yes, since the purpose of fog lamps is to illuminate the road surface in fog, they should be mounted as low as possible so the light can better reach the road surface instead of being reflected back into your eyes."

You seemed to have missed the rest of that point, where the use case for the fog lamp is not just to act as a fog lamp, but

"Such a high mounting position, combined with such poor aiming requirements, makes a good case for ... to use as auxiliary low beams.

As far as blinding myself, it is not legal to use fog lamps without low beams in PA. So the primary utility of a fog lamp for use in severe weather, is handicapped by the commonwealth.

In reading through older threads on this topic, the discontinued Hella XL Fog and the Bosch Compact 100 Fog have both been proffered to be somewhat suitable as auxiliary low beams, rather than purely used in inclement weather due to their having a pronounced central hotspot. That is my primary goal here. I do not see where auxiliairy low beams, like a specific low beam headlamp (e.g. a 4x6, 5.75" rd, etc) would be legal to mount and use, excepting the language in these statutes for vehicles equipped with snow plows. However a marked and compliant fog lamp would be, due to the wording of the law and the lack of stating they must be below the headlamps, as well as the loose aiming instructions (which, again, appears to have been written without much thought about how the two distinct types of lamps need to be used). SAE "Z" beam lamps are also exceedingly hard to find. It appears that there's still some places you can find sylvanias xenarc X1010 aux.low beam assemblys, but I don't believe those are marked as "fog" lamps, and frankly I'd like to stick with either halogen or LED.

A few generations of mustang have been notable for mounting their "fogs" at such a height. Not that that is a shining endorsement of such a thing, or a great example of performance, but the precedent has been set. And I can see such arrangements becoming more necessary as manufacturers begin insisting on mounting the headlamps closer and closer to the ground despite ample vertical real estate to maximize the height of lamps.

"What could possibly go wrong?"

Well, I could have a negative interaction with an officer which ends my use of this forum.
 
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-Virgil-

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Fog lamps really are not auxiliary low beams -- no matter what brand or model, where they're mounted.
 
turbodog

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I so wish that LEO in my state would actually pull people over for light violations. I've seen some really egregious ones...

Consider yourself lucky if your state enforces the law in this area. Could be a lot worse.
 
John_Galt

John_Galt

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Fog lamps really are not auxiliary low beams -- no matter what brand or model, where they're mounted.

Just basing that off your previous recommendations in older threads. This thread is partial thought exercise, partial examination of the codes as written, partial exploration of what exactly a driver could "get away with," due to such outdated laws.
 
Alaric Darconville

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If you want auxiliary low beams, get auxiliary low beams. They are far more useful than fog lamps. Front fog lamps range from very nearly useful to just plain decoration to "OMG turn them off, they're hurting more than they help"; they don't let you drive any faster than without them in the fog (since they don't really increase your seeing distance) and they don't make your car more visible to other drivers (your low beams do that). Under PA law, you can substitute fog lamps for headlamps in "conditions of rain or fog", but good modern headlamps do a fine job of lighting the road markings so you can creep along.

What you'll need is a good *rear* fog lamp so the guy in the pickup behind you who thinks his fog lamps help him see better won't rear end you. Installed, wired, and used correctly, it should improve your safety without incurring any problems.
 
John_Galt

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Again, there's no market for aftermarket auxiliary lows/SAE Z beams, and I'm not holding out for a set off ebay/craigslist were one to pop up. The sylvania x1010 lamp is interesting, however it's HID, and while it appears to still be available (NOS? maybe, or just old stock that never really moved) from one source, I don't believe it would pass muster, as its not marked "Fog." While attempting to falsify such a marking is technically feasible (say inscribing "SAE F" on a low beam headlamp module, or sae z-beam lamp), if a LEO were to take the time to search the product up, then they win when it becimes clear it's a falsehood.

While traffic enforcement is not as good as it "could be," and I am quite happy about that, not one for the state or its agents busying themselves extorting people, I'm alsonnot going out of my way to invite them into my life while purposefully violating the laws as written.

"What you'll need is a good *rear* fog lamp..."
I agree, however one of the codes aays they are only legal if they were an OEM option. I don't believe any of my vehicles ever offered such a a lamp, but I can check that again. Toledoupsguy had some good questions in the rear fog thread, however the greatest sticking point for an aftermarket unit is that it would need to run hot enough to ensure it stays clear, as a covered lamp doesn't help the situation any. I'm actually surprised the various LED models that have discussed don't offer a heated lens, given the conditions thwy would see use in.

As far as the statutes go, they're quite lax, and very poor for fog lamps, which is what would allow for the greatest flexibility of the lamps used/how they're used and when. For both myself and anyone else reading this thread later, I am attempting to get the clearest picture possible, so that a state trooper can get bent for wasting time if they take issue with lamp selection/install location/use.

Same with OEM LED assemblies. We had some seriously wet/clumpy snow that melted to and fully obscured my cx30's lamps on a short drive the other day. The last time I had that occur while driving I was coming through Erie in the middle of a blizzard, so stopping to clear my lamps occassionally wasn't terribly unsafe, as I was the only (idiot) on i90 driving through 18" of fresh lake-effect at 2 in the morning.
 
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-Virgil-

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I don't believe it would pass muster, as its not marked "Fog."

I'm not seeing a requirement in PA's vehicle equipment code for fog lamps to be marked "Fog" or "SAE F". Citation please?

Same with rear fogs:
one of the codes aays they are only legal if they were an OEM option

Citation please?
 
John_Galt

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@-Virgil-
"I'm not seeing a requirement in PA's vehicle equipment code for fog lamps to be marked "Fog" or "SAE F". Citation please?"

I thought the J583 standard was listed under 67 ss153.5 tables, it appears I was incorrect/misremembering. It appears there is no standard for what constitutes a fog lamp (brb, gonna mount a set of driving lights as fogs).

... rear fog legal if OEM option ... "Citation please?"

Vehicle Inspection Code 67 175.66
...((L)(3)) " (3) Auxiliary driving lamps and fog lamps shall be mounted on the front, spaced at least 20 inches apart from center to center and at height not more than 42 inches above level surface upon which the vehicle stands nor lower than the lowest chassis part. Rear fog lamps, if originally installed or offered as optional equipment, are acceptable."
 
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-Virgil-

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Wow, look at that. That rear fog lamp restriction must have been written by some clueless bozo.

I noticed the same thing when I looked at the PA code: no mention of auxiliary low beams, but also no definition of fog lamps.
 
John_Galt

John_Galt

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Pretty much anything appears to go for "fogs..."
 
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jzchen

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I live very far from your state and if I ever visit I guess I'll be looking at vehicle lighting...

Regarding aiming of fog and/or driving light, isn't "beam" meaning the entire beam, so that upper cutoff is below midline of the lamp, at 25'?

Regarding the 20" is it 20" from center AND 20" from any other lamp. This would really restrict the number you can just plop onto the front.

So the onus (if I used that word correctly) is on the owner to make it worthwhile adding such lighting....

Regarding rear fog OEM, isn't there an option for models destined for the EU? Daniel Stern's article on rear fog says it's been a requirement since the 70s/(EDIT- roughly 50) years...
 
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John_Galt

John_Galt

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@jzchen
"Regarding aiming of fog and/or driving light, isn't "beam" meaning the entire beam, so that upper cutoff is below midline of the lamp, at 25'?"

From title 67, subchapter 175.66 paragraph "L"
" (4) Auxiliary driving lamps and fog lamps shall be aimed when the vehicle and lamp assembly are in the straight ahead position with the beam not above horizontal centerline of lamp at 25 feet.

There's the rub. They included the same aiming standard for two types of lamps with two very different use cases, one which is arguably too high (for fogs, as typical aiming instruction is a 4" drop from lamp centerline at 25'), and the other too low, again placing the body of the driving lights hotspot aimed at the ground, rather than down the road, defeating the purpose of its install.

I stated previously that it thus appears that "anything goes" for fogs, however 67 175.66 paragraph "L," line 5 reads
" (5) A vehicle specified under this subchapter may have only one pair of approved auxiliary driving lamps and fog lamps."
. However I see no reference to anything at all referencing a standard (either SAE or otherwise) related to driving lights or fog lamps, anywhere in title 67 or Title 75, chapter 43 (ch.43 says they will establish standards... blahblah, nothing referenced). Under the tables listed in "67 153.5" there is a discussion of multiple SAE standards for lamps, but none that I see for fog or driving lamps.

So now it appears that perhaps there are No possible compliant fog lamps or driving lights, meaning every single vehicle equipped with them is in violation of the law... hopefully the state police don't stumble across this thread, they'll trip over themselves to start enforcing this.

Regarding the 20" is it 20" from center AND 20" from any other lamp. This would really restrict the number you can just plop onto the front.

No, I don't think it reads 20" center to center and 20" away. Most OEM vehicles couldn't meet that standard. 20" center to center minimum, not blocking/in front of a required/existing lamp, between a minimum 12"/lowest chassis height of the vehicle, and 42" maximum height (all measurements to center of the lamp).

Regarding rear fog OEM, isn't there an option for models destined for the EU? Daniel Stern's article on rear fog says it's been a requirement since the 70s/(EDIT- roughly 50) years...

That certainly is a good question. The laws text does not appear to require it be an OEM feature for US vehicles.
 
Alaric Darconville

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That mess of words they call "law" is a mess. For example:
A vehicle specified under this subchapter may have only one pair of approved auxiliary driving lamps and fog lamps.
Approved by who? The Federal law is that manufacturers self-certify their vehicles/equipment to conform to FMVSS 108, which neither requires nor regulates fog lamps. But because we Federally don't require type approval, States can't require type approval. What the State COULD do is proscribe the USE of the lamps, but not the presence. A lot of this stuff goes way back to the '50s and early '60s, before we had FMVSS 108.
 
John_Galt

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I suppose a benefit of this, we'll say ambiguity, to be as fair as possible, is that you could run a very good lowbeam headlamp to make up for poor vehicle headlamps, and mount them as high as your factory lowbeams, with an aim that is comparable to lowbeam aim, and still remain on "the right side" of the law. Considering the number of vehicles coming with poor rated headlamps, that's useful, at least for Pennsylvania registered vehicles.
 
John_Galt

John_Galt

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Anyone opposed to me slowly (as interest/time permits) doing this as a series of the different states "current" regs? Not 49 more threads, just dedicate an additional thread post and some ensuing discussion/clarifications/questions in here?
 
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toledoUPSguy

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What you'll need is a good *rear* fog lamp so the guy in the pickup behind you who thinks his fog lamps help him see better won't rear end you. Installed, wired, and used correctly, it should improve your safety without incurring any problems.
nobody will notice this :)
1647461867320
 
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-Virgil-

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Anyone opposed to me slowly (as interest/time permits) doing this as a series of the different states "current" regs? Not 49 more threads, just dedicate an additional thread post and some ensuing discussion/clarifications/questions in here?

Links to state codes/regs should go in a new post in this sticky thread. Discussion of state codes and regs should be in its own thread(s), like this present one.
 
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-Virgil-

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nobody will notice this :)
View attachment 25195

Why is the inside of your garage, in front of your truck, all lit up in yellow? What lights are doing that? And what's the list of lights on the truck that are switched on in this pic? parking/tail/side marker/license plate, obviously. Rear fog, obviously. What's on up front?
 

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