Running With Headlights Drain Battery?

[JerryBob]

I normally drive with my headlights on during the day for safety reasons. I heard it helps.

Without launching into a debate on whether it does (this is, after all, BITOG), I am wondering if I am shortening the life of the battery.

I notice that it is starting to crank slower when cold. It is the OEM battery, almost 3 years old.

 

[CharBaby]

IDK! The alternator may work OT but, I do the same and I can't tell. Most of my batteries outlast their total months rating!

 

[bigt61]

I think in DC, with all this crazy weather we're having, it's possible the alternator can't keep up if you're running all the accessories at once - wipers, heater, radio, lights, rear defroster, Nav, seat heater, etc. Especially if you're in stop and go traffic and idling a lot - the alternator isn't spinning fast enough. Give some stuff a rest for a few days and see if you can get the battery back up to snuff. Or the battery could just be getting old, but most OEM batteries last longer than 3 years.

 

[NHGUY]

You are wearing out your bulbs,all of them,wearing out the switch,and loading the alternator and regulator all the while I don't believe any survey has ever proven daytime running lights has ever stopped one head on collision.Every GM vehicle since 95 have had them,thousands have been killed in head on crashes in them ever since.I guess they need to question survivors in GM,Volvo,VW,Subaru...etc vehicles and ask them if DTRL did anything for them.

 

[JerryBob]

Originally Posted By: bigt61
I think in DC, with all this crazy weather we're having, it's possible the alternator can't keep up if you're running all the accessories at once - wipers, heater, radio, lights, rear defroster, Nav, seat heater, etc. Especially if you're in stop and go traffic and idling a lot - the alternator isn't spinning fast enough. Give some stuff a rest for a few days and see if you can get the battery back up to snuff. Or the battery could just be getting old, but most OEM batteries last longer than 3 years.


Sounds reasonable. I am in Fairfax, BTW.

 

[datech]

I have read that winter driving habits can run down a battery from excessive draw yet less charging, and the cold temps sap a battery, too.

You wouldn't think driving with the lights on would be less safe, at least if it is at all cloudy, rainy, foggy,etc.,so if you feel safer it's your option.

You might need to recharge your battery a few times during the winter. Overnight, maybe on the weekend. A trickle charger works well for this.

 

[BigCahuna]

I'm pretty sure that when your car was designed, it has had the total load for the vehicle calculated. it needs to handle the maximum load that can be applied.It wouldn't be worth owning a vehicle and paying big bucks for if it didn't. If your battery which you say is 3 years old, is loosing it's ability to maintain it's part in the system, I would have it load tested. Then have the output of the alt, checked to see if it is still doing it's thing.You can drain a battery down, also by not giving the battery time to recharge. Lots of start and stop driving will pull it down faster now that it's getting older.,,

 

[eljefino]

You'll be fine. You make full (or at least gobs of, 100+ amps) alt power at 2000 RPM which is just above idle, especially with an auto trans.

You'll know you have power problems if at idle the speed of your blower motor drops. The ear is sensitive to frequency and this is the first thing most people pick up on. Even then a minute or two at a red light isn't going to do your electrical system in.

A pair of headlights draws less current than the radiator fan, which runs a ton all summer.

 

[Pop_Rivit]

I always turn my headlights on when I drive (a holdover from a Lights On For Safety campaign). I've never had a premature battery failure.

 

[Fleetmon]

Good for you for running your lights for safety. It's not taking it's toll on your battery unless the battery is less than optimal anyway. We require lights illuminated on all of our fleet vehicles and historical data doesn't show an increase in battery or alternator use over the years and we have reams of data prior to requiring headlight use.

If one of our vehicles exhibits problems (as eljefino says - blower motor slowing down, lights dimming, etc at idle), I'd rather know about it on a nice sunny, warm day than in the middle of a storm.

Since you're noticing slower cranking, have the battery checked as suggested. A good battery and a healthy charging system can easily handle the load of lights. As a matter of fact, enjoy your radio and full-speed blower while you're at it....you're not hurting anything!

 

[Vikas]

Assume you are running 2 55W headlight bulbs. 1 HP is 750W. So you are using extra 110/750 or about 0.18HP. Asuuming your engine is rated more than 18HP, the effect of turning lights is less than 1%

But as amply demonstrated on BITOG, logic does not prevail here, only emotions do. So do what makes you feel good.

 

[cappilot]

I think the battery-draining question can be answered by anyone who drives a vehicle with a digital voltmeter. That is, the voltage remains plenty high (13.5-14.5V even at idle) to prevent a battery drain. However, the same voltage indication does not guarantee the battery is being completely recharged. Cold batteries do not provide as much starting energy as when warm, starting a cold engine requires more energy than when warm, and cold batteries do not recharge as readily as when warm. The end result can be a chronically undercharged battery, even though accessories are not draining the battery and the charging system is working just fine.

 

[Fleetmon]

Yet, batteries start our snow equipment that cold-soak at 10'+ F for hours and hours after running lights, blower motors, radios and a bunch of other accessories and when we get in them, they fire back up.

I looked at a set of batteries in an 2006 Oshkosh blower two nights ago and the batteries are the original equipment.....these two 8D batteries are firing up two Caterpillars with a combined HP exceeding 1k. We do however, use diesel-fired engine coolant heaters on a lot of equipment....although the heaters use up battery capacity, the engines turn over easily and fire much quicker. This particular machine I looked at, inexplicitly, had the heaters disabled.

 

[opus1]

Originally Posted By: Pop_Rivit
I always turn my headlights on when I drive (a holdover from a Lights On For Safety campaign). I've never had a premature battery failure.
Same here, only if it's sunny out I won't run with lights. Any clouds, I do. This is anecdotal research, but I got into the habit when I had a gray car and people would pull out in front of me on cloudy days like I wasn't there. When I started driving with the lights on, that problem lessened.

 

[shDK]

in Denmark where i live. you must have your headlighs on constantly, by law. we experience no problems at all. i know it is like that in sweden too

 

[Rolla07]

If its grey or cloudy out Id turn lights on. Beyond that DTRL are on anyways..I doubt it will drain the battery but have your battery tested. Mine is slow to crank but it still starts and my battery is 7 years old. Tested it and it tests almost new..

 

[otis24]

Putting it on a trickle charger, or a regular charger a couple times per year to bring it up to full charge makes a huge difference.

GM rep told us that he sent his dad in Florida a batter charger for his Hummer. Heat is very bad on batteries. He stated that his dad's battery lasted ten years in his Hummer because he kept it charged twice per year.

 

[dishdude]

You aren't hurting a thing by using the headlights. Don't be a car hypochondriac!

 

[bdcardinal]

You don't run off the battery when driving anyway, so you aren't wearing down anything except the bulbs. You can unhook the battery cables on a running vehicle and it will keep running, done it many times.

 

[Clevy]

Originally Posted By: bdcardinal
You don't run off the battery when driving anyway, so you aren't wearing down anything except the bulbs. You can unhook the battery cables on a running vehicle and it will keep running, done it many times.



I had a mustang with a bad battery for an entire summer. They push start easy thank god