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Why are rear light failure indicators not mandatory?

No car I’ve ever owned offers any sort of indication to the driver that a tail light or brake light is out. Why is that? Wouldn’t it be simple and inexpensive to detect this and have a warning light or problem message presented to the driver for either problem?



Not knowing that a brake light is out is especially dangerous, and I’m sure everyone has encountered the scary situation of driving behind a car that has no functioning brake lights.



It’s always been annoying to me that my car doesn’t notify me when a rear light is out. What gives?

There are some cars with “lamp out” warning indicator, Volvo is one. Next car you buy make this feature a priority.

Most people learn in driver’s education class to conduct a pre-trip inspection. If you don’t want to follow that sage advice, it isn’t too hard to check your lights when you check the tire pressure. If you don’t have someone to help you check the brake lights, you can either use a cheap mirror from K-Mart or Wal-Mart, or you can use something heavy to press the brake while you check the lights.

There are many cars that have the feature you want. If it is so important to you, you should buy one of them. Personally, I think there are enough idiot lights for people who don’t check their tire pressure, coolant, and oil. Taking proper care of my car isn’t very hard without these warning lights.

Why is there no warning indicator on a toilet paper dispenser? Nothing worst then finding out after the fact. :slight_smile:

Yes! You do, however, have some redundancy in that there are three brake lights. We have two vehicles that have dual 1157 tail lamps. One is a VW, the other is a Suzuki motorcycle.

If you spend enough for a car, you get LED stop/tail lamps; should last for the life of the vehicle.

A small hole in the front of a rear window 3rd brake light will give assurance that it is working.

You can head off brake/tail light failure by changing lamps once every year or two.

I have some surplus small diameter light pipe and am often tempted to route some from each stoplamp to where I can see it but have not done so on our cars but did so to a long gone motorcyle that had a single tail lamp.

Beyond that, yes what you say is needed.

As was already said, some makes of cars do have this feature.
In fact, my '74 Volvo had this feature, and it actually turned out to be more of a hassle than an advantage.

On that Volvo, the system compared current draw between two lamps on the same circuit. If it detected a difference in current draw, then the warning light on the dashboard would glow.

The problem was that the system was so sensitive that, even after I replaced a bulb, that damned warning light always continued to glow. As I finally figured out, a very minor difference in current draw between two different brands of light bulbs was sufficient to activate the warning light. So, since I was unable to find the same brand of bulbs that Volvo utilized in Sweden, each time one bulb burned out, I actually had to replace both bulbs on that circuit. Real convenient, huh?

Be careful what you wish for.

A small hole in the front of a rear window 3rd brake light will give assurance that it is working.

…so will seeing its reflection in the rear window at night.

My 1969 Corvette has center console indicators for the lights. They use fiber optic cables to transmit light from each lamp to the corresponding lens in the console. Can’t get much more reliable than that and way ahead of its time.

I’m not in love with my “failure to properly function” tire pressure indicator lights that NEVER seem to go out, regardless of how much attention the tires or the system gets…another glowing dashboard warning light for something I should check myself, no thanks. I just check them while looking through my mirrors at the reflections off my white garage door before driving away.

It’s a nice thought, but unfortunately it runs into the “two kinds of people” problem. People like us will check our lights with or without an idiot light (I do manual checks because even though my Volvo has a failure sensor, it’s so oversensitive that it can ping on temperature changes - I’m almost at the point of finding out exactly which bulbs it monitors and replacing every single one at once in an attempt to stop it showing up), while the other sort of people will cheerfully ignore the idiot light. Just think of how many people you’ve seen with their turn signals flashing at double speed - that’s a deliberate design to let you know that a bulb has burned out, and people just ignore the fast flashing and fast clicking. Or think of how many burned-out headlights you see - and that one is obvious the moment you turn the switch!

I personally think a worse safety issue than bulb failures is the regulations which allow the brake lights to double as rear turn signals. It’s not even as though the bulbs are that expensive, especially if you can buy in auto-maker volumes.

It has always been the driver’s responsibility to KNOW your vehicle is safe to drive BEFORE you drive it.
– all the rest is just babysitting –

YOU need to, at least visually, check the tires before driving off. The right hand side is the most ignored as drivers tend to just hop in and go. Check with a tire guage at least monthly.

YOU need to check you fluid levels occasionally.

YOU need to know if your wipers are good enough.

YOU need to know if your lights work. Monthly at least, Turn on the head lights, walk around and look. Even the little side marker lights.
Turn on your brites, go look.
Turn on the emergency flashers, go look.
For the brake lights I use my snow scraper pushing on the brake pedal, trapped against the front seat. ( or a helper )

YOU need to know that every passenger is seatbelted properly.

Especially in my case where there are multiple trucks and multiple drivers, it is MY responsibility, as a licensed driver, to visually “pre flight” the truck I haven’t driven in two weeks.

My '06 Escape has the bulb warning software in the lcd display, the 92 and the 79 do not, so I always check each truck and not wait for the babysitter.
Those babtsitting devices ( tire pressure, door ajar, seat belts, lamps out, etc.) can be an o.k. option but NEVER
NEVER depend on them totally or YOU are at fault.

YOU need to, at least visually, check the tires before driving off. The right hand side is the most ignored as drivers tend to just hop in and go.

The right hand side is also where most of the debris collects on the road.

Surprised I didn’t see my favorite “short-cut” mentioned here.

The next time you frequent a business with big glass windows (preferrably at night, but day should work too), do the following:

  1. Pull into a parking lot facing the window.
  2. Check: parking lights, full lights (both low and high beam), turn signals, hazards.
  3. When leaving business: turn car so rear faces window. Check everyting mentioned before, except add in brakes, delete high beams.

Saves you the walk-around, and it allows this to be a one-man job! The only thing this won’t help with is license plate bulbs (as they are indirect light). My experience has been that there are PLENTY of businesses with plate glass facing the parking lot…

Then, even if you’re not the one to personally replace the bulb, you’ll know what to tell your tech. ( ex, My wife would not change a bulb herself. She would tell either my daughter or myself and we’d ‘get-er-done’.)

Several cars offer this feature, it’s easy with todays on board computers. But you really don’t need it. Check them when you perform your PM. Any time I notice a window behind me at night I test all my rear lamps by reflection.