Photo: Daniel, Unsplash

The right way to jump-start a car

It’s a simple procedure, but using the wrong technique when jump-starting a car can cause significant damage.

We’re still not driving around as much as we used to – which means that many motorists are faced with a flat battery when they try to start their cars. This isn’t a difficult problem to solve; however, it’s important to consult the owner’s manuals to check if there are specific starting instructions, and to locate the jumpstart terminals, as an incorrect method can damage the car’s electrical system.

First, make sure the car (and the car with the booster battery) are both turned off, with the handbrakes up and gear selectors in park or neutral position. All headlights, indicators, car radios, and air conditioners should be turned off, and radar detectors and cell phones unplugged. Accessories from the cigarette lighters and power sockets must be removed. The cars should be lined up as close together as possible. 

Before proceeding further, check that the terminals are free from battery acid and wipe away any corrosion. Be careful, though: if you notice that the battery is cracked and leaking liquid, stop right there. A cracked battery might explode if you try to jump-start it.

Now, connect the battery jumper cables, remembering that the positive cable is usually red or orange, and the black or ground cable is traditionally black (although you should double-check that this is indeed the case in your car). One positive end of the jumper cable must be attached to the positive terminal of the dead battery, and the other positive end must be connected to the positive terminal of the good battery. Now, connect one negative end of the jumper cable to the good battery, and the other to a shiny nut or bolt on the dead vehicle. Note that the jumper cable should be attached to the negative terminal on the dead battery only if there is no other option, as it may cause an explosion. Run the now connected car batteries for a few minutes before starting the dead vehicle; then, allow the engine to run for up to five minutes so that the flat battery can pick up enough voltage to keep running once the jumper cables are removed. Before removing the cables, switch on one or two electrical components – like the lights – so that the voltage doesn’t spike, causing damage to the electrical system, and remove the cables in the reverse order. Turning off electrical components that may have been switched on will help the battery recharge while you drive a few kilometres to get the engine started again.