How long does it take hazard lights to kill a vehicle's battery?

My only experience was one time noticing a car with the flashers on, about 7 or 8 in the evening. The next morning, it was stone cold dead. I believe your kindness saved them a dead battery. And very often a starting battery completely discharged never comes back to life truly. So, you may have saved them from having to replace the battery next week. You are a good neighbor.

Not to discount the good Samaritan aspect of what was done, but those things have two batteries. I believe that they are designed with long standby while not having the engine running and having full lights on. Emergency flashers really do not pull that much. The small batteries in cars are their primary liability.

Nah...I just wanted to climb into the cab of a Cat! It's not something this big kid gets to do very often.

There are a ton of variables as well... how much amperage do the lights draw, what percentage of the time are they on while flashing, charge on the feed battery at the beginning, condition of the feed battery at the beginning, battery temperature and likely others...

Erik

Hi, If it were LED fhlasher, it'd last longer.

I agree with Nightcrawler on this one.

I was in my local battery shop when someone brought in a huge battery; much larger than a car battery. Just out of interest I asked what it was out of, and I was told it was from a Caterpiller Grader. They use those a lot here in Winnipeg for clearing snow. The guy told me that the grader doesn't just have one of those, but two of them. And, the reason why they have two batteries is because they're often left at construction sites overnight in the winter where there's no electricity available for a block heater. So, they need both batteries to provide the power needed to start their cold engines in the morning.

In fact, my understanding is that in Northern Ontario, they will often collect wood and start a fire under the engine of the graders and bulldozers to warm up the oil in the oil pan in order to start their engines in the mornings in winter. I've never personally seen that being done; I just heard that it is done.

I can understand that. I've talked to guys, and they say it takes ten minutes to learn how to use such a machine. And ten years to get good.

And if the flashers are LED or incandescent.

The good old days, we didn't need no stinken hazard lights, we had stinken road flares.

And how long do those newfangled road flares last? Not nearly as long as the kerosene lamps I remember from my youth, I'm sure.

Perce

LED bulbs draw much less current so battery would last longer

the batterys age makes a big difference too.

my 3 year old van battery died recently after the radio played for 2 to 3 hours.

i was cleaning and reorganizing my van.

I have a boost charger so it was no big deal, but it told me its time to replace the battery....

mine shouldnt of died so quickly, since i do the clean up the work van several times a year

Many years ago I worked in northern Wisconsin. One of my coworkers would arrive, start the oil draining while he disconnected his battery, and bring both inside the building. He was so skilled at these tasks they hardly added any time to his commute.

At the end of the shift he'd pour the warm oil back in, reconnect the warm battery, and start his car. Then often he'd jump the rest of us before he went home himself.

That's no longer necessary with the improvements in cars.

One of my coworkers would arrive, start the oil draining while he disconnected his battery, and bring both inside the building. He was so skilled at these tasks they hardly added any time to his commute.

back in, reconnect the warm battery, and start his car. Then often he'd jump the rest of us before he went home himself.

ments in cars.

Sounds like a bit of extra work. But, it did manage to get his car started when others would not.

Of course it would depend on the condition of the battery (or batteries, some construction equipment and heavy trucks have more than one) but any automotive or heavy equipment battery in good condition could easily run typical hazard lights for 6 hours. I've known of instances where they ran 14-15 hours, and certainly even periods are possible.

Any chance they had left the flashers on deliberately to alert motorists to their presence in the roadway? Playing Advil's devocate here . . . (-: I've seen that done before - leaving hazard lights flashing - when the equipment takes up a lot of road space and is being left overnight.

I much more impressed that you have the crew chief's cell phone number. You're a "total immersion" sort of guy. Now the important question is whether you call him during the day to find out whether you were a hero or not. You've made me curious. I always vote for hero but I even wonder whether you legally had a right to touch that equipment, even as a good samaritan.

It's a tough call. I am not sure I would have done it but I would agree there's a presumption it was accidental because both weren't flashing and any flashing lights would have to have been turned on during daylight, perhaps accidentally, and might not be noticed by a crew departing at

There's always more than one possible explanation. The driver might have been trying to get his boss to buy a new battery so he was deliberately killing this one before the real cold sets in and it could be a big hassle (that's for Clare - now I *am* grasping at straws, but for comedic effect).

So we have several questions for you to ask the crew chief:

Were they on by design/law/insurance requirement or on by accident?

Were they LED lights (you should be able to answer, flashing LEDs are very stroboscopic - not so with incandescent hazard lights. I would bet they are LEDs nowadays because they're on hazardous equipment and the extended run time - thus avoiding a dead battery if they're lit for too long - is a

Third question is how long those batteries last in such situations?

Fourth question - should you have entered the cab (his perspective)?

A topic for another thread might be whether replacing the tungsten bulbs in my old van with LEDs would preserve a significant amount of battery life in an emergency. I am not even sure that LEDs are legal substitutes for hazard bulbs or worse that they interact badly with the flasher electronics in this rather elderly (over 10 years) car and cause them to fail.

It might be better and smarter to retrofit a completely secondard LED based hazard light system, placing LED's inside the van's copious head and tail light lenses and wiring them back to a 12V gel cell and flash controller.

I recently saw a car with an amber turn signal LED on the outboard edge of the passenger side mirror. What a great idea. I might want that retrofit, too. The turn signals embedded inside the aforementioned lenses aren't anywhere near as visible as the tiny little outboard amber LED on the mirror. See what you've started wandering around in the dark, Derby? (-:

Speaking of calling you Derby I have to protest that I'm seeing TV news shows put up statements from totally made up names during "here's the buzz on the internet" segments they seem to be doing more often. Probably letting callers rant is about the cheapest form of programming available and station owners just love it. Just lamenting the state of modern journalism. When I watch the news and it tells me "ChickenMan23" said X about Y I wonder if end is nigh.

More straws. The driver is at this moment making a phony insurance claim for something he says was stolen from the Cat last night and the police are dusting for your fingerprints on the cab door right now. Your neighbor has already told police he saw you climbing on the equipment in the dark with two accomplices standing by.

(Sorry, I couldn't resist after the thread's beginning where it was posited that these men were out to rob you!)

Are you sure they didn't leave radio-controlled canisters of fentanyl sleep gas so that they could invade your home, knock you out by remote control and steal all your worldly possesions even if you were armed? Better start sleeping with a gas mask, just so S feels safe about your reckless decision to let them in your house. Dangerous Derby Dad, always living on the edge. (0-:

Re: How long does it take hazard lights to kill a vehicle's battery?

This made me think of "Blade Runner" where Deckard is asked by the Replicant Leon:

"How long do I live?"

Deckard replies:

"4 years" and the Replicant says

"Longer than YOU!" and proceeds to try punching his lights out.

One of the greatest lines in all Sci Fi movie history.

Depends on too many variables. How old the battery, how big, how many haz lights, what kinda bulbs, etc. My '91 toyota p/u's fairly new battery will go stone dead with haz lights flashing, overnight. All my bulbs are incandescents.

nb

If the Cat was parked in the street, it maybe a law in your state to have the hazard lights on overnight. If the battery died during the night and someone ran into the Cat, it would be their fault. If you turned off the lights, it would be your fault.

Modern car radios can take a surprising amount of juice. My vehicles don't even have an "accessory" ignition position. There is no way to play the radio with the engine off, once the door opens. But, yes, if it killed your battery in 2 or 3 hours, the battery was past due for replacement.