How to use jump leads

If you are a car owner, there are few worse things than getting into your vehicle when you are planning on going somewhere, only to find that the battery is dead and it wont start. This can be anything from a minor inconvenience to a major issue – especially if you have to be somewhere in a hurry.

Of course, if you have a set of jump leads, then it is possible that you can get yourself on the road pretty quickly. However, according to research from Green Flag, around 44 per cent of people don't know how to use their jump leads safely.

Jump leads can generally be picked up at most car-related stores for a reasonable price. But make sure you get some advice, don't just pick up the cheapest type as they might not be the most suitable for your vehicle.

Safety first

Before you even think of trying to get your car going with jump leads, you need to follow some simple, but exceptionally important safety rules:

• If you are in any doubt whatsoever about what to do then leave well alone and get some professional help, be it from a garage or from your own emergency service, such as Green Flag
• Check your vehicles handbook. While there are general rules for jump starting engines, some models have very specific procedures – and you should follow those under all circumstances
• While you are getting ready to jump start your vehicle, make sure you keep all metal objects away from the battery as this could create unnecessary sparks and could, in some circumstances, explode the battery. So be careful of watches, rings, tools or stray wires
• Don't try to jump start a battery that looks damaged – this could be very dangerous. Make sure you check the flat battery thoroughly for damage
• Avoid smoking and naked flames
• Make sure your jump leads are in good working order – if they are in any way damaged, don't use them as they can overheat and possibly cause a fire

Using jump leads

Once you are ready to start, it is important that you make some final safety checks and then follow the instructions below in the right order:

• Make sure the batteries are the same voltage before you connect the leads and make sure that the vehicles are parked with their handbrakes on and ignitions off. Also make sure they are not touching as this can cause sparks
• Remember GaBLE – Good and Bad, Live (+) then Earth (-)
• Connect the positive terminal on the 'good' car to the positive terminal on the bad (flat battery) car, using the live (red) lead before the earth
• Attach the black, earth lead to the negative terminal on the good car and then to a suitable earthing point on the bad car, such as the engine block or chassis, rather than the negative battery terminal of the ailing car. This earthing point mustn't be near the battery or fuel system
• Once you have connected the leads, wait a few minutes before starting either engine
• Start the engine of the good car and allow it to run for a minute then, with it still running, start the engine of the other car and leave both running at a fast idle for ten minutes
• Don't remove the jump leads while the engines are running as this can damage the electronics on either car
• If the jump leads get hot, switch off both engines and allow the leads to cool down
• Turn off the ignition on both cars and then disconnect the leads carefully in the reverse order. Be careful not to touch the clips against each other or against the car bodywork

As a final check, you should try starting the car that had the flat battery. If it wont start, then it may well have a more serious problem that will need the help of a mechanic or garage.