So I’ve come back from uni and my dad flattened the battery in the car (a new battery) and was recharging it back up. It was reading nearly full on the charger and I needed to go out so we unplugged it. The car wouldn’t start. We plugged the charger back in and it super low charge again. We then tried to jump the car using a brand new battery and it wouldn’t start it. Not really sure at this point what to do or what is wrong with it. Any help or suggestions would be greatly appreciated.

  • Does the dash lights appear? When do you try to start the car do you hear the engine cranking?
    – Martin
    Commented Dec 17, 2018 at 10:24
  • Yes the lights come on and the radio etc. but the engine cranks a little and then gives up Commented Dec 17, 2018 at 10:31
  • 1
    After the battery say sat for an hour what's the charge on it, anything below 10.50 then you got a bad cell in it, the next time you get a battery make sure you prime it, the batteries sit on the shelf in the store and all the electrolyte solution sinks to the bottom of the battery, leaving the upper half of the cells vulnerable to high heat, potential to blow a cell early, so it helps to tilt it and shake it slightly to stir up the solution again
    – user38183
    Commented Dec 17, 2018 at 10:42
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    You also may have a short in your electrical system, turn off the car and use a mutimeter on all the fuses, nothing should be using any voltage
    – user38183
    Commented Dec 17, 2018 at 10:47
  • When we plugged the charger back in it was reading around 13 Commented Dec 17, 2018 at 10:47

1 Answer 1


The 13 is irrelevant here! Watch the voltage when you crank over-it will drop This figure should not be less than around 10v -if it is, then the battery has no amp power to start the car and is defective, even if new

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