Discussions

my daughter's car battery is constantly dead. It was fully charged yesterday and completely dead again today. What can be causing this? Could something be pulling power while it's parked?  
 
Her dad put in an after market radio with bluetooth last december - the problem seems to be worse in the last few weeks.  
 
She isn't leaving on the lights or the interior lights. It wasn't plugged in today when she tried to start it but it's not that cold out.  
 
Please advise.  
 
Ker

Could just need a new battery. If it's old and worn out it won't hold a charge

How old is the battery? It may be time for a new one.

Yeah, mine too. I got a new vehicle quick charger for my phone. My battery died within a week. Recharged the battery but only last a few days. I finally replaced it and it seems fine now. I also didn't use the quick charger anymore.

Old battery or the alternator is bad. Check the dash display to see if it's charging while the motor is on.  
 
Make sure all of the interior lights are off when parked.

Check the casing for any leaks and fluid level. If it is leaking any fluid or low, the battery won't hold charge. A low battery "acid" amount is way more common in summer,but can also crack in winter if road is bumpy, and also can lose charge if battery isn't tight and secure in the battery compartment, as the thin plates in the battery can get damaged from vibrations. Most likely cause is what the others said: generator isn't charging, or defective or worn battery. Honestly, a lot of batteries are recycled core, and are crap. Went through 3 in a 4 year period a few years back with a C.T. battery. Get ours at Prairie Battery now, have no issues.  
As for generator/alternator, if you can get it out, you can have it tested at a few electrical shops in town. Sorry, unfortunately I can't remember the names off hand, but I am sure someone else on the thread can give some info.

Don''t even ask how I feel about batteries because I believe that most of them are crap. Used to be batteries were pro rated and we could buy batteries that had 60 or 72 month warranties, now you buy batteries that have one year or 18 month replacement, we bought one battery this fall, that in the last cold snap it froze up and was solid as a rock. Odd thing is sometimes you spend very little on a off brand battery that end up lasting an really long time, like 6 or 7 years.  
 
Guess I should add something that is on topic, and that is you can test and see if you have a very small loss of power by shutting everything off an disconnect one of your battery cables and use the tester between the cable and battery terminal, you need a tester though.  
 
Edited by don brown, 2016-12-30 18:54:46

I would say the battery is no good. You said it has gotten worse in the last few weeks, that would likely be caused by the colder temps we've had in that time. When a battery loses it's charge, they will freeze. You can boost them and it will seem to be charged but it won't hold it. To add on to Don's point on how to check for a draw, if you don't have a test light, often just unhook the ground cable and touch it to the side of the post on the cable, if there is a draw you will hear it snap (very quietly) and see sparks, this only works with everything turned off and make sure the radio and everything else is off,like clocks etc.

Take the car to Prairie battery on 18th street. They will test the battery for you for free right when you come in and then can tell you whether you need a new one or not. Then you will either know the problem or eliminate one option.

No one has mentioned and I forgot about - Are the contacts clean and solid? Check your terminals, they may need to be cleaned/tightened.

Personally the way I would check to see if it's the battery or something drawing off the power while it's parked over night is.. Drive the car to wherever and if the battery is charged enough to start the car then while parking it over night. Unhook one battery cable.. If in the morning when you hook it back up if it starts the car, then you know something was drawing down the battery.. If the battery is dead without having both cables hooked up then you know damn well the battery is hooped.. Just sayin.

I had this problem most of last winter. I bought a new battery and had the same thing happen...it would be dead every morning, even though I plugged in the car.  
 
I put a battery blanket on it and it didn't die at all after that.

Could be the alternator

Just disconnect a post for overnight, if it is dead in morning, the battery is toast.  
If it isn't my advice is to purchase one of those trickle chargers for retaining the charge.  
Plug it in with the block heater every night, it proved small voltage and will actually keep the battery warmer that the outside temp.  
You can permanently mount it and if you change vehicles take it and put in new one and use it as it will prolong battery life.

Bubbz said "I had this problem most of last winter. I bought a new battery and had the same thing happen...it would be dead every morning, even though I plugged in the car.     I put a battery blanket on it and it didn't die at all after that. "

I'm a huge fan of battery blankets. Your battery might still be done but these windchills that are coming this week are hard on a battery. It takes 5 minutes and $15 and your battery will act like it's the middle of summer... but that's just my opinion

something is draining your battery.......to prove this disconnect one battery post overnight and see what happens when you try and start car in the morning

Need maintenance. The posts need to be cleaned and the fluid topped up.  
 
Could be:  
 
- bad battery  
- corroded cables  
- low fluid  
- a drain  
- alternator

take power from the fuse box (or existing power), or did they run the power direct from the battery? My son had a friend install a stereo for him once, and this is what the "installer" thought was a good, easy way to get power. Killed at least one battery by drawing it right down when the car sat for a few days.