If your car won’t start because the battery has gone flat, then you may be able to get it going again by using this step-by-step guide to jump starting it.

Jump starting a car can be a safe job as long as you follow some simple rules. It is always advisable to check the owner’s manual before starting the job as some contain make/model specific instructions. If that is the case those instructions must be followed rather than any other advice.


  • A set of car jump leads (also known as booster cables)
  • Another car that is working well


Make absolutely sure that you keep metal objects such as rings, watch straps or other metallic items well away from the top of the battery as they can cause a large spark, which could potentially explode the battery and release the acid.

  • Do not try to jump start a battery that appears damaged or is leaking.
  • Do not light naked flames while undertaking this task.
  • Make sure that the jump leads you are using are in good condition – if they are damaged they can overheat and could possibly cause a fire.




Ensure that both car batteries are the same voltage and that they are parked close to each other with their handbrakes on and ignition off.


Connect the jump leads in the following manner:

A. Connect (+) positive red cable to the (+) positive terminal on the dead battery

B. Connect the other end of the (+) positive red cable to (+) positive terminal on the working car

C. Connect (-) negative black cable to (-) negative terminal on the working car

D. Connect the other end of the (-) negative cable to the (-) negative terminal on the dead battery


You are now ready to start the working car’s engine. Turn off all the electrical equipment on the working car (heaters, lights, radio) so that all the battery power is channelled in to jump starting the dead battery. It is best to allow the working car to run for a minute or so before you try to start the dead one. Revving the engine in the working car a little will produce more current and help with charging the dead battery.


After a couple of minutes of running the working car, try and start the dead battery engine by turning the ignition. If it sounds like it is going to start but will not quite go, then rev the working car a little more before trying again. Once you have the car with the dead battery running leave it to idle for 10 minutes.

NB: Do not remove jump leads while the engine is running as this may cause serious damage to the electronics on both cars!


After 10 minutes turn off both ignitions and disconnect the jump leads carefully. Do this in the reverse order to the way that they were connected:

A. Disconnect (-) negative black cable from the terminal on dead battery.

B. Disconnect (-) negative black cable from the (-) negative terminal on the working car

C. Disconnect (+) positive red cable from the (+) positive terminal on the working car.

D. Disconnect (+) positive red cable from the (+) positive terminal on the dead battery.


Once you have finished, you need to let the car that had the dead battery run for quite a while to allow it to build up charge again. It might be worth taking the car for a drive, or driving the car home and connecting the battery to a battery charger overnight.If the car will not start after following this procedure, then the battery could be damaged or faulty inside. To make sure it is a battery problem and not something else it could be worth swapping the dead battery with a borrowed one before you spend money on a new one.

Alternatively, get a mechanic or garage to come and look over the car for you.

Good luck!

Needs Breakdown Cover – GET A QUOTE HERE!