Jumper leads are a must in anybody’s emergency breakdown kit. Have you ever left your lights on by mistake, only to come back to your car to find that the car battery is flat and the engine is unable to start up? If you answered yes to this question, you are joining a club that has many members – including me.

Jump starting an engine is a common procedure whereby jumper leads/cables are used to transfer power from a good battery to a discharged battery. You will need help from another car to jumpstart a dead battery. To make sure the process of jumpstarting an engine is safe, connect the positive jumper cable to the positive terminal of the discharged battery first. Then connect the other end of the positive jumper cable to the positive terminal of the booster battery. Next, the negative jumper cable needs to be connected to the negative terminal of the booster battery before finally connecting the other end of the negative jumper cable to the negative terminal of the discharged battery.

Now try to start the engine of the car containing the discharged battery. Once the car has started, follow the reverse of the process mentioned above.

The jumper cables are heavily insulated, and need to be, because an electric shock from a car battery packs a punch. This is why it is important to connect up the dead battery first as described above. Otherwise, you will have jumper-leads waving around near you carrying a hefty charge and capable of giving you quite a zap.

If one, or both of the cars have any computerized components present in their engine, it is highly recommended that you make sure the jumper cables are surge proof. Power surges can occur through non-surge proof jumper cables and can fry engine computer componentry. Ouch – you have been warned!We hope that helps answer the question ‘What is What is a Jumper Lead/Cable?’!

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