Why does my car battery die if I don't use the car for a week?

Question

So tired of this happening. Basically, if I don't use my car for (I wouldn't even call it this) an extended amount of time, say, a week, the car battery simply dies! I have a subwoofer hooked up to the battery but I can verify that the amp is not left on. What should I do?

The battery is an Optima battery so its not low quality - also, this has occured over the years constantly with different batteries. Someone mentioned its because i have the sub connected well, so do millions of other people, you don't see them disconnecting their subs and lifting their hoods every time they leave their car..

Answer 1

oy have a parasitic load somewhere in the car or the battery is ****, i would check all your door switches and trunk switch to see if they are not turning off the dome lights, and check your radio and anything that some dumbass might have put in it throughout the years.

Answer 2

1. Check your batteries condition first by disconnecting battery cables and placing a slow trickle charge on your battery until battery is above 12 volts. Then...

2. If you don't have a battery load tester on hand, use a volt meter and check the voltage and right it down, IE 12.6 volts, wait a couple of hours. Then...

3. Check the voltage again, if it's below 12 volts you probably have a bad battery and it needs to be replaced. If it held the charge (over 12 volts) you have a draw somewhere and your battery is probably good...Or your alternator may not be keeping your battery charged. (when the car is running does your battery voltage on the gage go up to normal)?

4. If you have an electrical draw, insure your battery posts and connections are clean and on tight.

5. If you have an auto alarm system like a Viper or something, that will draw power and the only way to keep your voltage up is to operate your vehicle regularly to keep the battery charged.

6.When you say the car dies, does it die while your driving it or will it not start? Not enough info for me to keep going without more from you.

Answer 3

Question - did the battery issue start when you hooked up the sub-woofer? If so well..................

If not have you been a good citizen and helped jump a friend's car using your car? This is a common reason for battery related issues because cars are equipped with alternators not generators. What that means is that when two car electrical systems are connected the chance is that they are not electrically synchronized and the diodes can be damaged. Damaged diodes can leak current causing the battery do go dead if not used regularly.

It is also possible that you just have a bad battery.

Perform a test - When your battery is charged and happily working - simply disconnect the positive battery cable from the terminal and reconnect (that week later) before you attempt to start the car. If the battery is good the car will start.

OR - you can take your car to Sears and they will test the battery charging system - typically for free.

Oh yes, the recommended way to help jump a friend's car is to connect your battery to his/her car battery and allow your engine to run for a few minutes (without trying to start the friend's car). After a few minutes of your car's electrical system charging up the friend's car battery - turn your car off - leave the jumper cables in place - then start your friend's car. Once started remove the jumper cables before starting your car.

Answer 4

well it's parasitic amperage drain... If your subwoofer is not causing it then something else is. gotta do a parasitic amp drain test and isolate circuits while taking readings through your multimeter to find the one.
in short, somethings eating the battery, could be the battery is dirty, there is a lot of voltage that seeps out because of a dirty battery as stupid as that sounds.

I would clean your battery, get it tested to make sure all the cells are working properly.
Keep it clean and maintained, keep in mind that most batteries only have a service life of 2-3 years depending on temperature and usage.
Then start hooking up your meter, I don't know the type of car you're working on but you have to take into account airbags and transmission solenoids that only shut off after usually 20 minutes.
so make sure you let it sit before testing.

also are there any aftermarket accessories that might be installed improperly? that's where I would start looking.

Answer 5

THIS IS IMPORTANT!!! you are going to live your life in this cycle of "my battery goes dead
after a week of not driving" STOP! .
1. When a battery is at a discharge and
sits awhile like that it collects electrolytes
on the plates robbing the battery of valuble
charging surface.
2. DO NOT JUMP START IT (unless your in a hurry to get to work) It has to be charged on a low (2 amp) trickle charger for about 12 hours.
3. AN ALTERNATOR IS NOT A CHARGING DEVICE IT IS ONLY REPLACING
WHAT IS LEAVING THE BATTERY.
When you buy a new rechargable drill what does the instructions say about the first and every other charge? To charge it fully 100%
otherwise they will not perform as they are intended.

Or maybe your alternator is not putting out,.
A loose wire maybe..ANY CONTACTS THAT ARE NOT 100% CONTACTED WILL CONTRIBUTE TO THE BATTERIES DEATH.

Answer 6

You answered your own question.When you hook directly to the battery,you cause a drain.Just because a light isn't on,doesn't mean juice isn't being drawn.If you insist on leaving the thing hooked to the battery,I would suggest installing a quick battery disconnect switch to stop the severe drain.If the battery is good,and the alternator isn't smoked,this should help.Get both checked out.

Answer 7

You have a weak battery and cold weather or even really hot weather always akes a toll on batteries. The extras running off it may not help but the battery needs to be replaced. It's not holding the charge. If you jump it and don't run it a lot, it will always go dead again, it's not being built back up enouth to hold and the cold weather doesn't help either.

Answer 8

first, check the condition of the battery.. if the battery is no good, then put a new one in it..
if the stereo equipment was put in and is killing the battery, then something is drawing juice when the car is off.
if the stereo is not the problem, depending on the car, the on board computers drain the battery slowly. you may want to hook up a trickle charger while the car is in storage.

Answer 9

Put an amp meter on the battery to see how much current is being drawn.Pull fuses one at a time to find what circuit is pulling the juice.

Answer 10

you want to study your charging equipment, a sparkling battery will in trouble-free terms very last till it bypass's useless. Your charging equipment will keep your battery charged up, your charging equipment isn't operating. you may have it checked for free, like vehicle Zone, or everywhere like that. Walmart can examine it.