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How to jump start a car

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gices
Pa

When you’ve not driven your car for a long time or you’ve left your headlights on by mistake, you might find that your car won’t start because of car battery problems. Quite often all you need is a jump start to get you going again. Follow these easy DIY (Do It Yourself) steps and you’ll soon be back driving.

What you will need: jump start leads (one red and one black), gloves and a small brush for cleaning.

  1. First of all make sure both cars (the one with the flat battery and the car being used to provide the jump start) have the same voltage. Do this by checking the car battery. This is located under the bonnet but sometimes they are also found behind the back seats. To be sure refer to your car manual.
  2. Line the cars up side by side (if possible) leaving a space between the two. This is better than having them face to face as sometimes the car can jump forward and hit the other one.
  3. Open the car bonnet on both cars and make sure they are propped up securely by using the metal rod.
  4. Make sure that both cars have all appliances turned off for example lights, wipers and radio as leaving them on can cause them to short circuit.
  5. For the car with the flat battery make sure it is in first gear.
  6. Wearing gloves use the brush to clean all metal connections to the car battery (for both cars). In some cases you may need to remove plastic protectors around the battery.
    If any of the two batteries have acid corrosion or rust the power will not get through the cables and into the battery to revive it.
  7. The jump leads should be two different colours. The positive usually being red and negative black.
  8. First connect the positive lead from the car with the dead battery to the car being used to provide the jump start.
  9. Then connect the negative lead from the car being used to provide the jump start to the flat battery. When connecting the negative cables connect to shiny and non painted metal part of the battery on the dead car. On the car with the good battery connect to a shiny nut, connecting to a painted or dirty nut will not be successful. Do not connect the negative cable directly on the dead battery as there is a risk of explosion.
  10. Make sure there is no one near the car bonnet.
    Switch on the ignition in the car being used to provide the jump start and accelerate for 5 minutes. After 5 minutes switch off ignition.
  11. Try starting the car with the flat battery, remember to switch back to neutral first.
    If the car still won’t start try again for a further 5 minutes. If there is no success you might need a new battery.
  12. To remove the car leads do this in reverse order. Remove the negative from the car with the flat battery then remove the negative from the car being used to provide the jump start. Then remove the positive from the car with the flat battery then remove the positive from the car being used to provide the jump start.
  13. You can close the bonnet now.

Don't forget to thank the driver who helped you jump start your car. If the steps above did not help it may be a more serious problem, so the next step is to ask the mechanic at your local garage to come and have a look. In most cases you will only need a new car battery which on average costs around £65.

gices
gices Published 21 Dec 2007

2 Comments

gices 05 Feb 2008
Pat,
The jump start leads should pull the required amount of amps it needs. However if your battery is completely dead, it is better to get a new one as this will save you from breaking down when you least expect it.
Pa
PatWard 04 Feb 2008
I own a 2.4 diesel Volvo V70 and the battery is almost flat. I bought a jump-starter, charged it up and it won't start the car. The jump-starter is for petrol cars up to 4 litre engines and diesel up to 2.5 litre engines. In the Volvo owners' manual it says the battery is 800A but the jump-starter begins at 700A but goes up to 1500A. Is there a shortage of amps or should the jump-starter cope?