How To Jump Start Your Car Using Jump Leads

By David Sholicar

Here are 10 easy steps on how to start your car using jump leads.

Car jump leads

Here are 10 easy steps on how to start your car using jump leads.

This technique is easy to follow but a lot of people wouldn’t know where to start. Just remember, if this doesn’t work then there may be a problem with your vehicle which needs attending to. If that’s the case, it may be time to look into some vehicle maintenance. Book in for a full car service and let the engineer know that you have tried to jump start it unsuccessfully.

So, what do you do when your car won’t start?

Step 1

The first step in jump starting your vehicle is making sure that it is actually a problem with the battery. Take note of your headlights and dashboard electricals – Are the lights dim or do they flicker when your key is in the ignition? This is the first sign of a battery failure which can usually be rectified with an overnight charge.

Step 2

The next step is locating the vehicle’s battery. It will usually be under the bonnet towards the front right or left. At this point, take note of the battery’s positive and negative posts.

Step 3

Take the car you’ll be using for the boost and park it nose to nose with yours. It’s important that you have as small a gap as possible with a manageable space in-between. Do not let the cars touch.

Step 4

Safety is important as working with electrical components comes with risks. Make sure you’re wearing some rubber gloves and protective eyewear. After you’ve donned the safety attire, check the battery for cracks or leaks. If you do notice any imperfections then call a garage to be towed or replace the battery.

Step 5

Untangle your jump leads. Like most battery posts, one lead will more than likely be red and the other black. Once they’re connected to the batteries of both cars, it’s imperative that the positive and negative leads do not touch each other as it can cause serious damage to both vehicles.

Step 6

Connect the red, positive lead to the positive (+) terminal of the dead battery. Connect the other end to the positive terminal of the working battery in the other vehicle. Then connect the black, negative (-) clamp to the negative terminal of the working battery. Connect the other end of the black lead to a piece of grounded metal on the dead vehicle. Make sure you find a nut or bold that is not covered with paint or oily residue. There will more than likely be a small spark when connecting. As a last resort it is possible to connect it to the negative post on the dead battery, but there is a risk of igniting the hydrogen gas which will be leaking from it.

Step 7

Start the working car. Do not race the engine but rev it so that it's above idle for 30 seconds to a minute. This is done to charge the battery that has gone flat. Charging for this amount of time is a must. A good clean connection between the batteries is essential for this to work

Step 8

Try starting the dead car. If it doesn’t work at this point then turn off the working vehicle and check all the connections are good and secure. Start the engine on the working vehicle and charge for another 5 minutes and try again. If this does not work then it’s time to think about replacing the battery.

Step 9

Once both cars are running, disconnect all the cables in the following order;

  • The black clip which is connected to the grounded metal on the dead car

  • The black clip which is connected to the negative terminal of the good battery

  • The red clip from the positive terminal of the good battery

  • The red clip from the positive terminal of the dead battery

Make sure the steps above are completed in the order given to prevent accident short circuiting the batteries.

Step 10

Keep the recently started car running with your foot on the gas for at least 5 minutes and it running idly for another 20 minutes. This should give the car enough to charge to get going properly.

A full car service should pick up on any battery issues that you may be having so make sure you book your vehicle in as soon as possible after jump starting a car.

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About the author

Article Author Photo
By David Sholicar
David is the National Retail Operations Manager for Protyre. One of David’s areas of responsibility and expertise is dealing with the DVSA and MOT’s for Protyre. As the Authorised Examiner Designate Manager ( AEDM ) David deals with applications for changes to the many Vehicle Testing Stations ( VTS’s) including managing the growth of the Number of MOT testing stations that Protyre operate, allocating MOT tester roles, and monitoring the MOT Test logs to ensure that Protyre MOT standards are maintained as the best in the industry.
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