How to Troubleshoot a Bad Car Battery
- 1). Turn the key in the ignition and pump the gas one or two times. Sometimes a problem with your car that you suspect is the battery might actually be a fuel injection issue. See if pressing the gas pedal a couple of times gets the car started. Don't go overboard pressing the pedal as this can make it even harder to start some fuel-injected engines.
- 2). Listen to your car as you turn the key in the ignition. Is it virtually silent? If so, it could either be a completely dead battery or a problem with the starter---in either case, you need to take the car in for servicing because attempting to re-charge the battery probably won't help. Does the car make a clicking noise? If so, this could also be a low battery issue. Finally, can you hear it cranking slowly? If so, this is a clear indication that your battery just needs re-charging.
- 3). Turn the key to the "On" position but don't start it. Check the radio, dashboard and windshield wipers. If the radio turns on, the dashboard lights up (but dimmer than usual) and the wipers move very slowly, this is an indication that your battery isn't necessarily bad---it just needs re-charging. If none of these items turns on, you've got a bad car battery that requires replacement.
- 4). Look at the receipt for your car's battery to figure out its age. If the car battery is four years or older, it could be bad. That is the normal life span of a car battery.
- 5). Pop the hood and check the connections on the car battery. If they're corroded, that could be a sign of a bad unit that needs replacement.
- 6). Connect a portable car battery charger to your car (or ask a friend with a car to connect his battery to yours via jumper cables). Allow the battery to re-charge for at least five minutes then attempt to start the car. If it turns right over, it's not a bad battery---it just needed a re-charge. If it's still cranking or silent, even after a few more minutes of charging time, then it's probably bad and needs replacement.
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