Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Blinding bright tail/ brake lights... super bright LED's too bright?

A lot of new cars have super bright LED brake lights. I think some are too bright, and after sitting behind some cars at stop lights, they leave me seeing spots like a flash bulb went off in my face. How bright can brake lights be? Is there a limit? Will the new Cadillac have lasers or maybe photon torpedos?

Not a new problem. I remember my dad complaining about the '76 or so Pontiac Lemans in front of us, GM did a good job back then maximizing the tail light brightness.

Heck, I just invested in new LED rear lamps for my old 79 chevy stepside pickup . Best thing I ever changed/upgraded away from OE on that truck.

Now I don’t get honked at when the drivers back there are too lazy to take a look at the little square boxes bolted to the sides of my rear fenders.
Maybe for them I should also add a third brake light on the roof edge.
( but the more non-OE the truck gets, the less it’s worth as a classic )

What do those drivers do to an even older classic vehicle when only one rear lamp was legal ?

Some of the LED brake lights have no diffusion so they look like an array of intense pinpoints.
Even though the total light output isn’t so high the peaks are bothersome.

“Some of the LED brake lights have no diffusion so they look like an array of intense pinpoints.”

Don’t the tail light lenses diffuse the light?

All of the lighting requirement for uatomobiles are compiled in Department of Transportation DOT-108. Here’s a link to the site. Enjoy.

Whoops, I guess that was just the index. You’ll have to do the research from there. Sorry.

with so many distracted drivers, they need all the help they can get to prevent rear end collisions

I have not had a problem with super bright led lights. I don’t mean to be rude, but you might check with an eye doctor.

“I don’t mean to be rude, but you might check with an eye doctor.”

Maybe. But tolerance for light is so personal. Some folks actually like bright lights. I Do Not. I always put the rear view dimmer on when I leave the neighborhood in the morning. I leave so early that the sun is just coming up even now.

That’s what I want, stoplights so bright to make people stop about 15 feet behind me instead of 3 feet. I was rear ended at a stoplight a while back and have some paranoia now. I always had a little after I saw a series of about 4 cars at a stoplight that were stopped too close together get rear ended when some idiot forgot to stop; hit the rear car that hit the next car etc.

JT, what you say is true but the suggestion to see an opthamologist (NOT an optometrist) is an excellent one. I can tell you from personal experience that sensitivity to light can be a symptom of degenerative eye diseases that if caught early can be treated. Vision once allowed to deteriorate cannot be restored. Prevention of vision loss by having your eyes checked regularly, and especially if any question whatsoever exists, is the only way to prevent deterioration.

NOTE: an opthamologist is an eye surgeon; an optometrist, while they can check for pathologies, is basically a refractionist. A good optometrist is fine if you know your eyes are healthy and your goal is just a new prescription, but if any question exists or if (like me) the age of fifty has disappeared long ago in the rear view mirror, an opthamologist is the way to go.

“Don’t the tail light lenses diffuse the light?”

A lens or reflector with a fine pattern of small facets can scatter the light in many discrete directions.
Not quite the same as the random distribution of a lightly frosted cover.
Some designs do better than others.

How bright can brake lights be? Is there a limit?

Your govmint at work regulating automotive lighting.

Those LEDs in tail lights are wimpy compared to something like an OSRAM diamond dragon at full power as just one example. We design these types of LEDs into emission sources for analytical instrumentation using metal core PCBs and huge heatsinks to keep them from burning up. You’d fry your eyeball if you looked at one without protection.

I’ve been seeing an ophthalmologist for decades; every year. Fortunately for me, my light sensitivity is about normal and there are no issues with eye disease. Still, I have to use the rear view mirror dimmer at night and I prefer using sunnies during the day.

Hysterical TT. Hey, we have huge buildings chock full of very serious bureaucrats whose entire function in life is to write these things…under the guidance of the lighting industry and vehicle industry lobbiests and engineers, of course.

I was reading an article in a car mag recently that talked about the necessity for a car company to design different taillights for models to be sold in the U.S. because our required surface area is slightly different than the European required surface area. Laughing is the only way to remain sane.

JT, unfortunately for me I have glaucoma. But it’s been caught, I’ve had two surgeries on each eye, and I hope to grow old at least being able to see myself doing so in the mirror. Had I not had regular exams by an opthamologist, my future would probably be very different.

“… unfortunately for me I have glaucoma.”

It is very lucky it was found in time to save some vision. My sister had a detached retina and several operations - all to give her peripheral vision in that eye. The things she went through to keep the retina from detaching again were just awful. I’m a very lucky guy.

If you don’t think these lights are too bright, you haven’t been stuck behind one of these cars at night at a stop light, or maybe you just don’t get out much. I drive at night in the city a lot (300 miles a week) and I don’t see them every night. I think they are a danger. They will make you see spots (like a camera flash), you have to look away, it’s blindingly bright. I will pay more attention to the make and models of the cars, it’s not a lot of them, they are new cars. There is one model of Cadillac, one might be a Nissan or Lexus. These lights are BRIGHT RED !

As one ages their sensitivity to light changes also. When I hit 42 I started wearing glasses. Then around 50 I started noticing that real bright light bothers me. I wear sun glasses all the time when I’m outside. I asked my ophthalmologist about it…he said it comes with age…Just live with it.

If you read the standard, they have provisions for adjusting the brightness based on ambient light (e.g. dimmer at night) for exactly this reason.

If you don’t think these lights are too bright, you haven’t been stuck behind one of these cars at night at a stop light, or maybe you just don’t get out much.

You missed one possibility- some people can resist the urge to stare at them. To steal a line from Seinfeld (in reference to staring at female headlights) it’s like looking at the sun- you don’t stare, you get a sense of it and then LOOK AWAY.

When I was living in England, I was so sick of people being so close to me I couldn’t see their headlights anymore, I actually mounted four red fog lights in my rear window (two up high, outer corners, two more or less where the third light would be), and connected them to my brake lights.

That pretty much ended people crawling up my rear.

May not have been legal, but cops never stopped me (for that), and it passed inspection. Had a couple comments that it looked like a Christmas tree…it was a 4 door Corolla…pretty darned small, so you know they had to be trying to push me.

Of course, that was years ago…when I was much younger and quite a bit dumber, I’m sure…but I didn’t know it at the time. :slight_smile: