Hello,

My girlfriend has the car parked all day. She started it to come and pick me up (no problems). She parked in front of where I work. She turned the car off and left the fans on inside the car (hot air), so that the windows don't fog up. She was listening to a CD. About 3 minutes later, she got out of the car to scrape off the snow build up on the windshield and left the music and fans on.

Remember, the car was not on when she was parked.

4 minutes after, I got into the car and turned the key. It started, but the starter was cranking very slowly. After being started, I noticed the battery light was on. I drove about 500 feet. Then, the car lost power slowly so I pulled to the side.

The battery was dead (could only turn the starter slowly). My dad got us started with booster cables and we drove fine without problems (the battery light wasn't even on).

What's the deal?

2003 Echo, probably the original battery (I'm not the original owner)

I guess my question is, should 7 minutes of the char being off while the heaters are maxed and a CD is playing kill a battery in minus 35 degree celcius weather?

This post was edited by Xtopia on Feb 2 2011 03:38pm

it could very easily especially in cold weather, and even easier if the last few rides its been on have been short.

if the last few trips involved quick short trips then the alternator didnt have enough time with the battery so its charge could have been hampered...

but yeah... the cold weather... running shit while car isnt running(stupid idea)... you brought it on yourself.

Yes, definitely. You've got an old battery and you're trying to start it in extreme conditions. Car batteries should be replaced at least every five years (manufacturers recommend replacement every 3-4 years). Your battery is eight years old. Compound this with the fact that it was likely a factory-installed battery and not one designed to handle cold weather, and I'd say your battery almost certainly was drained.

After a car starts, the battery won't begin charging immediately. You need the engine to reach higher RPMs to charge the battery than idling generates. When in very cold weather, I make sure to take a slightly longer route if I know I need to take a short drive, and make sure that during this I keep the engine above 2000 RPMs as much as possible. I'm pretty sure the engine needs to be running at more than 1500 RPMs to charge the battery as a general rule, and idling will only reach around 1000 RPMs.

right. 1500-1800 and itll start charging your battery.

but the general rule is to not be running stuff with the vehicle off.

leaving the fans and music without running the car can drain the battery

happens to my car sometimes, which is why i usually leave it idling now

how many cold cranking amps is the battery? was the enigine still cold when she shut it off? takes alot of power to turn over an engine in the cold. once its on it starts recharging. the battery was drained enough to not want to start your car, especially with the CD player and heater most likely still turned on when you started it.

great idea to turn your CD and anyhting else off when you turn off your car. drains the battery when your car must not only turn your car on, but power these devices as well when you turn the key. after you turn it on, these devices run off of the alternator, not the battery.