1st day driving the Prius. Left headlights on for 5 hours, battery drained.

my 08 with #2 turns of the headlight when i open the door to exit. check the manual. Sure you turned off the car power??

 

did you exit the car through something other than the driver's door?

 

In Australia the headlights turn of automatically if you open the drivers door after you power down the car.
For this to work you must not open the door before powering down the system. Beware if you are a person who reverse parks with the door opened.

 

Same with the U.S. version. You always want to check and make sure the lamps are really out.

Tom

 

I thought the headlights also went out even if you opened the driver's side door and then turned the car off.

 

I never tried that.

 

Congratulations on the new Prius and welcome to PC.

I turn off the lights as a habit (I turn the lights on everytime I drive) after turning off the car.

 

There is a sequence issue where sometimes the lights don't go off. You may be right for this particular sequence, but what is important to remember is that is easy to accidentally override the auto-shutoff feature. Never assume that they will go off; always check.

Tom

 

if you turn off headlights and then turn them right back within a sec, they will not turn off.

i think you have other issues going

 

Always lock the car after you get out. That way it will beep at you if any doors are ajar or if the car is not powered off.

Sorry about the dead battery, but things will get better!

 

Same here in the states. But I never could understand, that as advanced as the Prius is, that there are so many opportunities to kill the 12 volt battery. In my 1997 Ford F-150, all the lights (interior and exterior) would extinguish after 40 minutes of inactivity with the ignition off. Simple. You would have to try real hard to kill the F-150's battery. Why the Pruis does not incorporate some sort of system to prevent a dead 12 volt battery is beyond me.

And while were on the subject of batteries, same with the HV battery. Most of us know on this board not to push the car if you have run out of fuel because you may damage the expensive HV battery. But I'd be willing to bet most Prius drivers are not aware you can possibly damage the HV battery if you run out of fuel. That's one reason I'd always be wary of a used Prius; hmm, has the HV battery been stressed because of an out of fuel situation in its past history??

So why can't the Prius figure this out too? Just like a conventional automobile, when you run out of fuel that should be the end of the line. Why does the Prius allow someone to damage the HV battery in such a situation??

Rick
#4 2006

 

Not following you here. You say "left the headlights on at 6:30 AM. It probably turned its self off"
Not sure what that means as this car has no delayed on & off. It won't turn itself off later. And the hatch has nothing to do with the headlights either.
Its very simple. If you open the door before you shut the car off the lights stay on. Its an excellent system. Leave the lights on. Shut the car off....then open the door...get out..and lock the car. In that order. Always without exception lock the door. It will beep if you have a hatch ajar or left the car in ACC or On. Oh and read the owners manual.

 

Ed,

He left the lights on. He could tell because of the position of the headlight switch. In his initial post, he assumed the headlights drained the battery. After reading Fusco's post and remembering his actions of the day, he realized that the battery went dead because he did not properly close the hatch.

 

I leave my lights on 24/7 for safety. As soon as you open the DRIVERS' side door, with the power off, the headlights go off. The only time I ALMOST killed the 12V batt was when I opened the passenger door and powered up to do some quick cleaning while listening to public radio (that's the side of the car next to my house and front walk). I powered down and closed the door and went inside... Came out later and apparently caught it JUST before the batt totally drained, since the headlights DON'T power off if you just open the passenger door. Wouldn't start at first and window opening with ACC ON was very sluggish. I left it with lights off for an hour or two and she started right up. I drove her a bit to make sure the 12V got well charged and she's had no batt problems since.

I think you somehow were powered up with the passenger side door open, and the lights stayed on. Just be careful of that and you can otherwise leave the headlights on.

 

Thank you so much for your post!! You saved me...
A friend was kind enough to call me and let me know my headlights were on. After <3 hours, the hybrid battery was down to "2 bars" according to the energy screen. From your post, I knew I couldn't just wait until the next morning...
Just goes to show how small the hybrid battery is.

 

:welcome: Welcome to PriusChat, bmoerdyk2, but you are mistaken about the hybrid battery, or rather, the high voltage Hybrid Vehicle traction battery. It's quite substantial, and it's also completely disconnected from the car except when the Prius is in READY mode.

The headlights, radio, and other low-voltage equipment runs off the small 12V battery. It is rather dinky and can be drained fairly quickly if you leave something on. It is always connected to the car and provides a tiny bit of power all the time to maintain your radio station settings, the clock, the SKS system, etc.

The little battery is charged by the big battery. The big battery is charged by the engine and regenerative braking. If you leave your car in READY with the lights or AC on, the engine will automatically start to charge the HV battery when it gets low, perhaps as low as one purple bar. As long as you have gas, the car will keep the HV battery from getting too low. If you ever run down your little battery, put the car in READY for at least 20 minutes. Go for a drive.