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Dublin: 12 °C Sunday 15 September, 2019

How to jump start a car

Follow these tips to safely jump start a car.

GOT A FLAT battery? Here’s how to jump start your car safely.

First off, make sure the battery on the other car has at least as much voltage as the flat battery.

Do not jump start a hybrid car.

Get started

Open the bonnet of the car with the flat and try to manoeuvre the other car as close as possible so the leads reach both batteries but make sure the two cars aren’t touching.

Put both cars in neutral, put on the hand brakes, turn off the lights, air-con, other electronics and the ignition and take the key out.

Keep the clamps away from each other at all times, and keep other metal objects like rings and watches from touching the battery terminal to prevent the battery from short-circuiting.

Source: Shutterstock/Checubus

The charging

Put the black clamp on the negative terminal of the charged battery.

Put the other black clamp on to a suitable earthing point on the flat car – an unpainted, oil-free metal part in the engine bay, away from the battery and vehicle’s fuel system.

Why don’t we connect positive first? Well, the negative could spark and cause damage if you touch it off anything when the positive is already connected.

Put one of the red clamps on the positive terminal of the flat battery.

Put the other red clamp on the positive terminal of the charged battery.

Wait a few minutes for the voltages to equalise. Start the flat car. If it doesn’t start, remove the key and start the charged car and let it run for a minute, then start the dead car. Let both cars continue running for a few minutes.

Breaking contact

Don’t remove the jump leads while both the cars are running.

Turn the charged car off and then remove the leads in the opposite order that you connected them. Red off the charged car, then red off the flat car, then black off the flat car and finally black off the charged car. Again, make sure you don’t touch the clamps off anything.

Make sure you drive the car for a good half hour to charge up the battery. The longer you drive it the better.

READ: Part two of our 162 new car guide

READ: Car hack – DIY mobile phone holder

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