car battery goes flat?

ummmm.... make sure you turn off everything in your car

like stereo, lights, and a/c or heater when you get off the car

then if dont solve it check the altenator which charges the battery

if there is no problem then its gonna be the battery

if you had for not too long ago bring it back to where you bought it and then tell them to recharge it or exchange it for free

First you need to know if your battery is damaged or expired. If it's not sealed, open it and use a flashlight to see inside with the front lights on. If you see any bubbles, your battery is shot.

Maybe you have a short in your vehicle, not so big as to blow a fuse. Disconnect one of the battery terminals and in between the battery and the cable, connect a small lightbulb. It shouldn't light on (not even a bit) when everything's off in your car. If it happens, you've got a short which needs to be found and fixed. Another option is that your alternator / regulator are faulty. You need to check those with an ammeter while the car is running but you need to know how big the charge should be. Or check the battery voltage with the engine running. It shouldn't be under 13.5 V. Good Luck!

Funny you should say that!!

Being a very clever sort of feller I had the same problem last week, but worked it all out , it couldn't be the battery because I checked the charge rate, it was good, mine didn't refuse to start after a few hours ,some times it started other times it wouldn't!I found a swift kicking around the front end area of the car was of no benefit at all??

Every one was telling me it's a duff battery, I was getting very frustrated asking why do you think that?

Their many and varied answers contained no logic at all.

So what was the prolem?

It was a duff battery, I bought a new one , no trouble since!!

Sounds like your battery is old (like others have said). Could be a bad cell, but age usually just requires a new battery. Your cell phone is fine if its a newer battery, older ones are more sensative to current drain (leaving headlights on only takes 5 minutes instead of 25 minutes to kill the battery)

notes: If your alternator was faulty or broken your car's electrical system wouldn't function after you started the car. If the car starts and the vehicle runs fine until you shut it off, the alternator is not the problem.

Engine running - alternator generates electricity to power headlights, instruments, engine controller, radio. (also charges battery)

Engine off/during crank - battery provides electricity to move the starter motor to get the engine started.

What is your car? Most modern ones will need about 11 volts to make the computer start the car. Sounds like a new battery is required, better still buy a car without a computer and the problem is non existent as most old cars will start with only about 9 volts.

Check your battery: Unscrew the lids on the cells to see if they are dry, if they are top up with boiled water so that it just covers the cell inside each hole.

If that does not help check your alternator with a voltmeter, it should charge about 14 volts. If significantly less like 12 volts it is broken and must be repaired or replaced.

If the alternator is not the problem meaning that it produces sufficient power(approx 14volts)and topping up the battery does not help you will need to replace the battery.

Note: Not all batteries have lids that can be opened, if it does not it is a so called maintainance free battery and must be replaced. But check the alternator before deciding to do that.

Sounds like something is draining the battery down. And the charge system not working properly. If the battery is old, it could not hold a charge any more. . . sounds like you'll need to replace the battery. Start there anyways!

sounds like a dead cell, buy yourself a voltmeter (£5 Qd's) or borrow one after going for a drive take a reading, then ten minutes later take another reading ( do not start car) if it is draining rapidly say anything under 12 volts is draining and will not start your car.

Do you have a stereo in the car that you leave on and only comes on with the ignition on? if not make sure you have not turned it down and forgot about it, sounds silly but i have seen it a couple of times now.

could be several things a bad cell in the battery a short in the electrical system of the car draws the battery down. take it and get the battery and the electrical system checked.

YOU COULD HAVE A BAD CELL IN THE BATTERY. YOU SHOULD CHECK FOR A SHORT. SOMETHING MAY BE STAYING ON. DO YOU LEAVE YOUR CELL PHONE CHARGING IN THE CAR. THAT WILL DRAIN THE BATTER. SOUNDS LIKE THE BATTERY IS GOING. IF IT IS 3 OR MORE YEARS OLD REPLACE IT.

You need to check the output from the alternator and replace the battery as it sounds like it has a dead cell.