The headlights on my 4108 are dim. I'd venture to say that they are really dim. High beams are only slightly better than low beams.
Are there some common places to look for problems with the headlight circuit?
My goal is to keep the OEM headlights for now. Any suggestions would be most welcome.
You can try polishing your lenses. That will help if they are getting foggy. Some people use toothpaste but any fine grit will work. If you need more power, you may want to check your ground wire as it may be rusted a bit. There are other solutions, but you should check your ground first. Maybe run a test ground wire from your battery to your light socket and see if it gets brighter. If so, the ground may be the problem.
poor ground. try a direct ground jumper to confirm.
low voltage, bad relay, usually.
12v or 24 v, and what gauge wiring to the headlights? what are the voltages when the bus is running (alternator on) and lights are on? Grounds? And what kind of headlights? Old school incandescent, or quartz halogen, or new LED's? I solved my personal crappy headlight issue with some excellent 28 volt Cibie Halogen lights. Most times, bad headlights are voltage drop to the lights from bad grounds or too small gauge wiring, plain old worn out bulbs, or a bad 24 volt to 12 volt conversion (what I had). Plus, what was once acceptable is now simply not, perfect old headlights now seem unusable.
I'll measure and confirm voltage levels tomorrow. Same with the grounds.
There is a small panel in the tool compartment under the driver which my manual indicates is the mounting place for the lighting circuit breakers. Would this be where the relay is as well? Or, is there one in the electric panel to the left of the driver?
Headlights currently in the bus are the OEM 24v sealed beam headlight. Wiring is stock. I don't know the gauge off hand. Plugs on the back of the bulbs are tight and clean. I'll have to track down the ground contacts tomorrow.
Quote from: richard5933 on October 22, 2018, 06:56:23 PM
Headlights currently in the bus are the OEM 24v sealed beam headlight. Wiring is stock.
which allows for smaller wire.
I would also check the resistance of each wire involved.
corroded 50 year old wire can be hard to isolate.
This equation, i = v/r, tells us that the current, i, flowing through a circuit is directly proportional to the voltage, v, and inversely proportional to the resistance, r. In other words, if we increase the voltage, then the current will increase. But, if we increase the resistance, then the current will decrease. :)
We always solved that problem on Eagles which were crappy too by adding relays for each light.If I recall the 28v head light are 60/80 watts a drop of a 1/2 to 1 volt will make a huge difference in brightness.I saw buses before some one had installed all four lamps the same model and number on the 4 light systems it sucked on bright
They seem dinner compared to current headlights. Take an accurate voltmeter and check voltage at headlamps before spending time looking elsewhere. Since your coach is in such great condition, I expect the option is to go with different lamps. I haven't found any led headlamps in 5 3/4 diameter out there in 24 volt. Other sizes, yes. One option is to convert headlamps to 12 volt and use halogen or led. Changing to 12 volt on Buffaloes is easy. Where those relays are in under driver's compartment, GM had a plug and play resistor panel that enabled the option of using 12 volt headlamps. You install panel, plug it in and replace headlamps with 12 volt units.
The only question I have is that different bulbs will draw different currents affecting voltage at bulbs, especially LEDs. Probably worth a try if Luke has a take off resistor panel.
Of course, this is assuming you don't have a votage issue with current headlamps.
I put in 28 volt quartz halogen lights. The lights themselves are normal Cibie lights, and the bulbs are available from Daniel Stern. About as good as bus lights are going to get. That said, these look very interesting - 9V to 32V, DOT approved, these would be the high/low beams, not the high beams. That is a very common motorcycle application, you may not find (or need) the equivalent high only beams. https://genssi.com/5-75-5-3-4-in-led-black-projector-headlight-round-dot-v2-set/
If my reading of the manual is correct, the headlights that came stock in the bus have the following power draw:
Low beam: 37.5w / 55w
High beam: 37.5w
I've been in touch with DanialSternLighting and they do have modern lens/housing assemblies with replaceable bulbs that will work on 24v. Sounds like they would be a drop in replacement, at least for the most part. However, the bulbs run 70w each, which is nearly twice what my wiring is designed to handle. Guess that could be handled by installing a few relays and heavier gauge wiring from the 24v power tap to the relay and on to the headlights.
My first step will be more basic - if the weather holds today I plan to pull the relay/resister panel and check all the connections, as well as check the ground connections. All the other lights (clearance, etc.) run bright and clear, so I'm hoping the problem with the headlights is just a weak connection or sticking relay somewhere.
Like I said, buy a volt meter and check voltage at bulbs before you start taking things apart. If you change to other headlights, go with led. They are far brighter and draw less current.
LED's are nice for the driver but suck for on coming traffic and coming up behind you,some states are cracking down on those, here you get a repair ticket with so many days to dim the lights and I like that in the desert a little light goes a long way
The problem I see with LED as an option is fitting them into the existing buckets. The sealed beam lights are fairly shallow, and the LED lamps look like they carry quite a bit of junk in their trunk.
The issue with LED lights and blinding oncoming cars is that most of them are not actually approved for on-road use. They are available in formats that do not blind other drivers, but those are much more expensive.
My first plan of attack will be to fix what I've got. If I can make them work like properly functioning sealed beam headlights I'll be okay for now. I drove with them for decades on cars with no problem. We rarely drive the bus at night, so getting the current setup working should suffice for now. If not, I'll explore other options.
Voltage readings hopefully will follow later today.
Voltage plays a huge parts those lights are rated at 28 volts for full brightness,they are supposed to sell the LED's by the lumen but skirt around that and tell you the watts.I bought a pallet full of LED's (7in) from a military sale it took me for ever to sell those @ 10 bucks ea because they were 2000 lumen and not legal for hiway use
After doing the research and then the installation of solar panels I have become acutely aware of the importance of having the correct size wire for 12/24 volt accessories. Prior to that I never gave wire gauge much thought. But having under size wire can make a huge difference especially with lights. Of course, with the bus wiring being 50 years old condition of existing wiring should also be suspect.
OK - I give. Can anyone point me to the place where the headlights make their ground connection?
For that matter, there are supposed to be a couple of grounding lugs in the electrical compartment next to the driver. Can't find them either.
Also - I have the resister panel in the tool compartment, but there are not any breakers like the manual shows. Anyone know where they are?
Voltage at batteries with engine running and lights on is 27.11v and at the dimmer switch is 26.0v.
Obviously a voltage drop. Not sure if it's a normal drop or the cause of the problem, but for sure it's not helpful.
I measured at the dimmer for two reasons... 1) It was handy, and 2) it eliminated any problems from the as-yet not found ground connection for the headlights.
Regardless, the wiring to the headlights looks really clean and everything seems tight. I know, that's going to be the car until I find a problem. Now on to go search for problem areas and/or bad ground connections (if I can find them).
I have no idea about head light grounding on a GM bus that said some buses the lights are relay grounded that confuses the hell out of me
I don't think that there is a relay in the circuit. Seems like the headlights are wired directly to the switch.
The only things I see in the circuit are:
Circuit breaker > Switch > Dimmer Switch > Circuit breaker > Low Beam
> Circuit breaker > High Beam
Can circuit breaker cause a voltage drop? Do they fail slowly or all at once?
UPDATE: I found the ground posts in the driver's electrical panel. Those are both tight and clean. Looks like the ground from the headlights is there.
I've thought about adding a relay, but where would it go? Would it help to add relays since the wiring run is really pretty short - just from the driver's electrical panel to the headlights?
Or, what about increasing the gauge size on the wiring? Right now it looks like the entire headlight system is wired using 16 ga wires. There appear to be separate circuit going to each headlight though, and no one light appears to carry more than 5 amps. From the charts online, 16 ga wire can carry 5 amps the required distance with only a 3% voltage drop. That might be what accounts for the voltage drop, so maybe going to 12 ga would reduce the voltage drop and increase the lighting.
One more thought - today I checked the voltage drop and found 27.11v at the batteries and 26.0v at the feed to the headlight dimmer. What I did not check was the voltage at the driver's electrical panel main feed buss. Guess that would be something important to check, and it's on my list for tomorrow. I want to check to see if the drop is between the batteries and the electrical panel or between the electrical panel and the headlight circuit. If it's in the headlight circuit it's easier to fix. If it's between the rear and the front of the bus then it will be a more difficult fix.
In other words, I'm really confused about this and don't know what to do first to make things better. Rather than guess, I'm doing nothing for now until I come up with a workable game plan that will actually improve things.
You have 12 volt headlights. That is what the resistor panel does. Check a headlight bulb, it should be marked 12 volt. That panel should have multiprong plug that plugs into coach harness. at top of resistor panel are your circuit breakers.Check your wiring diagrams. The ground connections come off at headlamp bulbs, not under driver's compartment.
Now there is the possibility that you have the panel, but still have 24 volt lamps. If so, the harness coming down towards the panel will have a plug with short looped stub wires, and resistor panel is not plugged in. If that is the case, unplug stub and plug panel into it and change 24 volt headlamps to 12 volt.
Quote from: chessie4905 on October 23, 2018, 04:33:47 PM
You have 12 volt headlights. That is what the resistor panel does. Check a headlight bulb, it should be marked 12 volt. That panel should have multiprong plug that plugs into coach harness. at top of resistor panel are your circuit breakers.Check your wiring diagrams. The ground connections come off at headlamp bulbs, not under driver's compartment.
Now there is the possibility that you have the panel, but still have 24 volt lamps. If so, the harness coming down towards the panel will have a plug with short looped stub wires, and resistor panel is not plugged in. If that is the case, unplug stub and plug panel into it and change 24 volt headlamps to 12 volt.
Are you certain about this? I thought that I measured the voltage at the headlights when I first started this thing and got something around 25v. Possibly the high beams were on and I was measuring across two hot terminals?
If what you say is correct, then I should measure approx. 12-13v at the headlight socket, correct?
There is a loom of wires coming from the resistor panel, and it does go through the multi-prong harness plug like you mention. No looping of wires. It does seem that the circuit breakers for the headlights are all located in the driver's electrical panel on this bus, not above the resistor panel.
Funny thing is that the resistor panel is not anywhere in the wiring diagrams, at least not that I can find. Sure would make the solution easy if that is the entire problem - nothing more than a trip to the local parts store to get the proper sealed beam lamps.
With engine not running (but battery charger on), headlight socket has 9.8v. I'll put the block heater on later today and start to engine to see what the reading is with the generator and all circuits fired up. I know that the headlights are noticeably brighter with the engine running.
Regardless, it does seem that chessie4905 hit this on the head - resistor panel is reducing voltage to the headlights to 12v. The headlight bulb is labeled 12v.
So, now my goal is to figure out how the resistor panel is wired into the headlight circuit. First I'll see if there is a bad connection somewhere. If that doesn't help I'll try to figure out how to replace the resistor panel with something more modern to provide proper 12v to headlights.
If you look at the photo of the resistor panel I posted earlier, you'll see that there are lots of wires coming to/from it. The resister panel is somewhere in the circuit after the dimmer switch. I've got to figure out where things go after that. I know that the four circuit breakers are 5-amp each and mounted in the driver's electrical panel. Not sure where things go from there, but I'm assuming to the resistor panel.
Still looking for a wiring diagram for this if anyone has one they can snap a photo of.
I know you like to keep things original but resistors are a poor setup for headlights,your getting 9 volts now in hour of running when they build heat that will be 8 volts .I would be looking for another option like a 24v Vanner and use the 12v supply from it
Quote from: luvrbus on October 24, 2018, 05:42:47 AM
I know you like to keep things original but resistors are a poor setup for headlights,your getting 9 volts now in hour of running when they build heat that will be 8 volts .I would be looking for another option like a 24v Vanner and use the 12v supply from it
Actually, I am looking to replace the resistors. This would come under the category of safety equipment, which I have no problem replacing with modern equivalents.
For simplicity, I think it would be easiest to just replace the resistor panel with a modern 24v-12v converter. Problem is I have no idea how the current panel is wired into the system. There appear to be 6 wires in and 6 wires out. Where are they coming from and where are they going to?
Best I can tell, the resistor panel sits between the final circuit breakers and the headlights themselves. No certain on that and will have to do additional checking. I'd like to avoid rewiring the complete headlight circuit, and hopefully someone will have information about how this thing is currently wired so I only need to adapt what's necessary to modern parts.
Keeping the 12v headlights is certainly a goal though, as they can be found anywhere should I ever need one.
I'm thinking that one of these should do the trick. Probably overkill for now, but if I upgrade the lights to something better down the road I'll be ready.
https://www.donrowe.com/Samlex-SDC-30-DC-DC-Converter-p/sdc-30.htm
Now if only I knew how that resister panel fits into the wiring harness so I don't blow something up replacing it.
GM had a thing about using resistors just amazes me they did it on a headlight system,I remember the problems they were on the 55 Chevy's going from 12 to 6 v on the coils
A little snug on capacity, you are at the rating with 4 x ~75 watt bulbs burning, easy to do with good high beams.
Remember who was maintaining that coach after it left the factory... a collection of characters who were, for the most part, unsupervised. The lights were working once the greasy hands were done, that's all the foreman cared about, but the methods used to achieve that...
Many techs, when faced with a problem in the headlights, would change it over to whatever they liked, there was an ample supply of 12 and 24 volt parts lying around the garage back then.
Expecting to find a stock configuration at this point...?
I like Cibie brand too, excellent optics, puts the light where it belongs.
RJ prefers the E-code ones, if he would get off FB and join the real busnuts on the forums, more often, he would tell you himself...
happy coaching!
buswarrior
Quote from: richard5933 on October 24, 2018, 06:02:54 AM
I'm thinking that one of these should do the trick. Probably overkill for now, but if I upgrade the lights to something better down the road I'll be ready.
https://www.donrowe.com/Samlex-SDC-30-DC-DC-Converter-p/sdc-30.htm
Now if only I knew how that resister panel fits into the wiring harness so I don't blow something up replacing it.
I spoke with Luke this morning. He thinks that this an option installed at the factory. Unfortunately, he says not all options made it into the wiring diagrams.
Looks like four wires go in and then out of the resistor panel. I'm guessing that they separated out each of the four wires in the system (left low, right low, left high, & right high) so that any failures could be contained to the single lamp.
I'm going to verify later today. If this is correct, then it seems I could either use one larger voltage reducer upstream, or use four smaller ones to replace the resistors, maybe 20 amps each.
For now I plan to keep as much of the existing wiring in place as possible and continue running the 12v sealed beam lamps for now. But, by getting the right voltage reducers I'll be able to upgrade the wiring and lamps down the road.
We used imilar DC/DC converters on 24v Cat/Dirt eq. to power 12v Motorola Com radios.
I would remove the resistor and use one after I eliminated all other possibilities.
It sucks to tear out and have the same problem when you are done.
Worst case, I would power the bus lamps with my truck source 12v or a 12v battery on a good charger and troubleshoot.
I may be full of sh*t on the 12 volt option. Those resistors may be for daytime running lights running at reduced brightness. Do you have them? When I get a chance, I'll check the wiring diagrams to determine one way or the other.
Quote from: chessie4905 on October 24, 2018, 10:51:55 AM
I may be full of sh*t on the 12 volt option. Those resistors may be for daytime running lights running at reduced brightness. Do you have them? When I get a chance, I'll check the wiring diagrams to determine one way or the other.
Best I can tell, the daytime running lamps only work when the engine is running. There is a tap from one of the generator terminals which has 12v output. It goes to the low-beam terminal on the dimmer switch, but through a diode. The diode prevents the 24v of the headlight circuit from back feeding to the 12v terminal on the generator when the headlights are turned off.
Seems like they ran the 12v to the headlights to provide half-power to them for daytime use. I'm going to have to confirm this, but my guess is that the resistor panel is in the circuit immediately behind the headlights themselves. They serve to cut the 24v input from the bus in half so that 12v headlamps can be used. When the daytime running lamp circuit is providing the 12v input, the resistor panel cuts it in half which provides 6 volts to the 12v headlights.
My guess is that if I replace the resistor panel with modern 24v-12v reducer(s), the daytime running lights won't function. I'm debating whether to install one large 24v-12v reducer upstream from the headlight switch, or keep the wiring basically the same as it is now but replace the resistor bank with four individual 24v-12v reducers (left low, right low, left high, & right high). Either way, the modern 24v-12v reducers are designed to provide a steady output, usually something around 13.8v, when there is an input of 20-30v. With the 12v input from the DRL circuit they would do nothing.
I'm heading out to the bus to do some more inspecting and voltage checks. Will report back with what I find.
Spent a few hours checking voltage and running through the circuits checking for problems. Here is what I found:
Circuit design: The flow goes as follows...
30a 24v Breaker > Headlight Switch > Dimmer Switch > Circuit breaker > Resistor Panel > 12v to Low Beams
> Circuit breaker > Resister Paenl > 12v to High Beams
Resistor panel:
There are six pairs of resistors. The panel has four input/output conductors.: two for low beam and two for high beam on both input & output. I took apart the panel so I could test each resistor pair, they are all labeled with their resistance, and each tested spot on.
Voltage Drop
There was about a 1.5v voltage drop from the start of the circuit to where the power entered the resistor panels when I started today. After cleaning, tightening, and using DeOxit to remove oxidation I got that down to about 0.4v voltage drop. Still not perfect, but better.
At the end of the day, I was able to get the voltage being output to the headlights from 9.8v up to about 11.5v. Still not where it needs to be, but certainly a great deal better. The headlights have gone from being virtually useless and downright dangerous to just weak and not up to snuff.
Plan moving forward:
I like having 12v headlights. This gives me many more options for replacement bulbs and future upgrades. There is just so much better availability in the 12v headlight world.
That said, I'm going to spend some time this winter investigating options for replacing the resister panel with a more modern 24v-to-12v voltage converter method. i like that they used four separate circuits to feed the headlights - if the resistors in one leg fail I'd be left with three working headlights. A failure in this setup isn't catastrophic. I'd like to go with the factory setup and wiring for now, but with replacing the resistors with something like this:
https://www.donrowe.com/Samlex-SDC-15-DC-DC-Converter-p/sdc-15.htm
four of these would be fed from the same four circuits that currently feed the resister panel. Then I'd upgrade the 16 ga wire from the output of the converters to the headlights to 12 ga wire to avoid any loss after the converter. These convertors will output a consistent 13.8v to the headlights with an input from 20-30v.
I could also use one much larger 24v-to-12v converter to supply the 12v to the system much higher up in the circuit, probably after the initial 30a circuit breaker. However, by putting the converters just before the headlights in the circuit, any voltage loss would be minimized since they will output 13.8v even with a slight decrease in their input.
i would still check ohms/resistance of individual wires, if you have not already.
dimmer switch leads a nasty life, my bet is it is good for some losses.
adding some modern relays and getting the amperage to run the lights out of the switch and dimmer will also help the cause.
happy coaching!
buswarrior
Quote from: eagle19952 on October 24, 2018, 04:58:31 PM
i would still check ohms/resistance of individual wires, if you have not already.
Done - wires and connectors are pretty good. I cleaned up the ones I found with issues using DeOxit
Quote from: buswarrior on October 24, 2018, 05:03:03 PM
dimmer switch leads a nasty life, my bet is it is good for some losses.
adding some modern relays and getting the amperage to run the lights out of the switch and dimmer will also help the cause.
happy coaching!
buswarrior
Still wearing its wax/rubber coating underneath. Didn't find any noticeable voltage drop across it.
I'm still thinking the big problem is the resistor panel just not having a steady and reliable output. By switching to a more modern electronic converter, I'll have consistent 13.8v output to the headlights with an input of 20v-30v.
Quote from: richard5933 on October 24, 2018, 05:27:00 PM
I'm still thinking the big problem is the resistor panel just not having a steady and reliable output.
Resistors, look easy to change, are cheap.
Why couldn't you get a guru to calculate the voltage you want ? and replace them ?
A head lamp will survive 14v and be just that much brighter.
And the lamps are almost free if they last a little shorter life.
Resistors of that size aren't going to be cheap.
Resistors also throw away power, just waste it in heat. Maybe power is free when the bus is running, but still...
I would be for tossing the resistors and do the upgrading,they waste power and drop voltage the longer they are in use under power,years back when Ford used resistors in the heating and AC units you could hear the fan slowing down after running a while.Resistors in a head lamp system makes no sense interesting. I think the MCI center tap from 24v to 12 v would be better than that and I don't care for the center tap much
resistors,, well they seem to have worked well for 40 years...
nothing lasts forever.
converters don't either.
Quote from: eagle19952 on October 25, 2018, 07:43:46 AM
resistors,, well they seem to have worked well for 40 years...
nothing lasts forever.
converters don't either.
Lol I doubt they were 100% effective for 40 years with that type draw from the headlamps
Resistors could be prefect but don't match today's headlights. The system is setup for the resistor resistance to match the headlight resistance so you have the same voltage drop across the resistor and the headlight. If the modern headlights are more efficient, then they probably have less draw and you get more drop across the resistor and less voltage at the headlight.
The Samlex 24v-12v converters are nice, but they are large and pricey.
Since the headlights are divided into four separate legs and each leg doesn't carry that high a current, I'm thinking about using four of these: https://www.amazon.com/dp/B01LY8D7U0/?coliid=IZCHLZO0I1H6W&colid=1K5E0RD2YQ7ZJ&psc=0&ref_=lv_ov_lig_dp_it
Not that fond of using imported electronics, but I'd be using these at far less than their rated current limit.
Anyone have experience with something similar? Or maybe someone has a better suggestion for a converter?
I just installed this one for my King Cruise Control, electric sunvisors, cigarette style socket, and pulse air wiper control. Nice unit and has a flat fuse on it for protection.
https://www.amazon.com/Power-Step-Down-Converter-Technology/dp/B003P17X8I?ref=silk_at_search
Quote from: chessie4905 on October 25, 2018, 06:43:12 PM
I just installed this one for my King Cruise Control, electric sunvisors, cigarette style socket, and pulse air wiper control. Nice unit and has a flat fuse on it for protection.
https://www.amazon.com/Power-Step-Down-Converter-Technology/dp/B003P17X8I?ref=silk_at_search
PYLE has been known to make good stuff :)
What is the downside to using 24v headlights? Maybe carry a spare of each? I realize they are expensive but wouldn't that be cheaper and more reliable/less complex than a voltage reducer?
Jim
You can buy Hella housings and install led bulbs . Just find the ones that are rated at 24 volts. Some are rated at up 32 volts. You can buy bulbs at whatever brightness you want to live with. Since they draw less current than factory incandescent bulbs with less heat, you can use the original wiring.
Superbrightleds is one place to get the bulbs, and there many others on Amazon and Ebay.
Yeah, but there's a problem with those LED halogen replacements. LEDs still don't have anywhere near the point density of a halogen/tungsten filament, so the source is more spread out. That means the lens optics are not right and there is more light scatter. And that puts the hot spot of the light beam where it doesn't belong and you can't entirely correct it with headlight aim. Sort of makes them illegal if anybody were to look close enough but at the very least other drivers won't like it.
Jim
Quote from: Jim Blackwood on October 28, 2018, 11:41:47 AM
What is the downside to using 24v headlights? Maybe carry a spare of each? I realize they are expensive but wouldn't that be cheaper and more reliable/less complex than a voltage reducer?
Jim
1) Availability: 24v headlight bulbs are nearly impossible to find when on the road. It's possible to order them to have on hand but most of what's out there today is intended for either military or off-road use. That's what I understand is the reason the buses went to 12v - they could no longer have a steady supply of headlamps. I have a set of 24v bulbs, but they are definitely off-road bulbs and I don't think that they're DOT certified. Light pattern is probably not correct or optimal.
2) Most 24v headlamp bulbs, especially military bulbs, are actually 28v bulbs. At idle, my system doesn't produce enough juice to keep them at full bright, and even at highway speeds I'm not sure I'll be able to get them at their brightest.
3) Current setup is for the 12v bulbs. Want to keep it that way.
4) With the electronic 24v-13.8v converters, I'll have a steady 13.8v with an input voltage ranging from 20v-30v. Headlight output should be optimal at any engine speed.
5) When I want to update to somewhat more current technology down the road, 12v is much easier.
6) I enjoy the challenge.
Other drivers are going to get used to it, like it or not. Even the city busses here use leds. If you get couple of led bulbs, or complete headlamps, you'll never look back. The same thing was said when incandescent headlights went to halogen or projector lights or hid's
Well, no that's not really the issue. There is no question the LED is a superior light source. The problem is with the beam pattern. That's one place where America has always been behind Europe and as far as I can tell, for no good reason. We are every bit as capable of making good optics for headlights but we don't. In fact if you really want the best optics you still might have to go back in time to the old Marschal housings made in France. But to be fair, Hella and Cibie have gotten nearly as good though it's certainly taken long enough. That's with Halogen elements though and if you move the element even a millimeter out of the sweet spot it throws the beam off.
That isn't much of an issue with typical American optics where all you have is a roughly oval blob in the middle, but with good optics you have a sharp cutoff at the top and an angled down left side so that you can put maximum light in your lane without blinding oncoming drivers. So to do it right you need a housing designed and manufactured specifically for a correct light pattern with an LED source. Hella and Cibie may have those by now but if so they aren't going to be cheap. Figure close to a hundred bucks each if not more. Those cheap ebay specials you see have no cutoff optics at all and as such are probably illegal to use on the road. In fact I have trouble seeing how some of the new car LED headlights ever were approved but enforcement has been getting more lax for decades so maybe it shouldn't be a surprise. It can't go on for ever though, the same concerns that created the standards in the first place are bound to resurface.
Jim
Along with spay and neuter your pets...
Refuse to run lighting that is not DOT compliant.
Cheap lights never were DOT compliant, whether we talk 1965 or 2018...
Remember "aircraft landing lights"?
Please choose good quality compliant lighting, whatever that means for your price point!!!
happy coaching!
buswarrior
I don't want to be 'that guy', the one that totally disregards the ability of other drivers to see the road and safely make it home.
The European standards headlamps don't appear to be a problem, although their pattern is different from the DOT standard.
LED?? Right now it's really hard to tell which are DOT compliant and which are not. Some of the bulbs are compliant, but only if used in housings that are compatible with the LED light pattern.
So, for now I'm going to stick with the sealed beams. Eventually I'll probably upgrade to DOT Hella or similar housings with halogen bulbs. I don't drive the bus at night for the most part, and my goal right now is to get the sealed beams optimized as best as possible. I've driven for decades without LED headlights, and I think I can make it another little while.
And, I agree. The wild west attitude towards headlights will have to come to an end eventually. Sadly, it is probably going to take a couple of major accidents with multiple injuries due to blinding oncoming headlights to convince the industry to get a handle on things.
The problem with LED's as headlights is that the pattern emitted by LED bulbs is totally different that bulbs or sealed beams and even projector headlights. And at this point in order to use LED's effectively and legally you have to use the housing as well. And I"m not aware of LED replacement UNITS for the original sealed beam headlights.And where replacements are available(i.e. Kenworth) they are pricey.
The 4104/4501 and rectangular light peeps have options:
https://www.grote.com/products/90941-5-grote-7-inch-led-headlight-sealed-beam-replacement/
http://www.truck-lite.com/webapp/wcs/stores/servlet/CategoryDisplay?storeId=10001&urlLangId=-1&urlRequestType=Base&categoryId=13091&langId=-1&catalogId=10002
The 5.5 doesn't get any attention
happy coaching!
buswarrior
5.75. They do have dot compliant led headlamps for trucks. Saw them today. Hella makes Ecode headlamp housings that will take leds and in hi-lo and hi. You could use halogen if you don't care to use leds. If adjusted properly, they won't bother other drivers. Some of the leds, btw can be rotated in the housings to get a better beam pattern.
What you really need to be able to choose a good light is information on the actual beam pattern. They all do have that data, it's just a matter of getting it.
Jim