The tools you’ll need
To jumpstart a car, you will need:
- Jump leads
- A different vehicle with a charged, working battery (it’s recommended that you don’t use a hybrid or electric vehicle to jumpstart your car, as doing so can damage the on-board electronics)
- Rubber gloves
- Safety goggles
Before jumpstarting your car
Jumpstarting needs to be done safely and carefully, just like any mechanical job. Before you get cracking, remember:
- Never remove jump leads whilst the engine is running (this can severely damage the car’s electrical components)
- Avoid using jump leads that are damaged
- Don’t jumpstart a car while wearing clothes that dangle, or are made from metal e.g., scarves, rings, necklaces
- If the flat battery looks damaged or is leaking, do not attempt to jumpstart it
What are the symptoms of a damaged car battery?
A damaged car battery will often demonstrate one or more of the following:
- Corrosion on the terminal caps (caused by leaking battery acid)
- Rotten egg smell when lifting the front hood (result of hydrogen sulphide gas)
- Swollen case
How often should you change a car battery?
If a car battery is significantly damaged, it should be changed instead of recharged. Batteries typically last between five to seven years, so if yours is around that age and is showing signs of deterioration, it’s time to replace it.
Dim headlights, multiple turns being required when trying the ignition, or the car struggles to start, are common signs that a car battery is not working properly.
Step 1: Park your cars together
It’s time to get your two cars lined up and ready. Park them close enough that the jump leads will be able to reach from one battery to the other, and keep the handbrake on. The ignition should be turned off while jumpstarting the flat battery.
Step 2: Connect the jump leads
When using jump leads, it’s important to first put on your rubber gloves and goggles, to protect yourself while connecting them.
A jump lead will come as two cables: a black one, and a red one. These need to be connected to the correct terminals on each battery.
Attach one end of the red jump lead to the charged battery’s positive (+) terminal, and connect the other end to the flat battery’s positive terminal.
With the black jump lead in hand, connect one end to the negative (-) terminal on the charged battery. The other end needs attaching to an earth point well away from the battery or fuel system, such as unpainted metal on the chassis. Some vehicles may have an earthing rod, so check the manual to see if your car has one.
Step 3: Start the cars
The next step is getting power flowing to the flat battery. Before doing this, leave both engines off for three minutes.
After this time has passed, start the car with the charged battery and leave it for one minute.
It’ll then be time to start the car with the flat battery. Turn on its engine, and leave both cars to run for approximately 10 minutes.
Step 4: Disconnect the jump leads in reverse order
The flat battery will now be charged. Switch off both engines and disconnect the jump leads, starting with the black lead. Don’t let the leads touch each other, or the car, as you do this.
Step 5: Check the charged battery
Now that the process is complete, turn on the newly charged battery’s engine and check if it starts. If it does, let it run for 20 minutes and then head for a short drive.
If the car with the recharged battery still doesn’t start, it’s recommended to get help from a professional mechanic, as there could be a different issue that needs assessing.
With our guide, your car’s flat battery should now have a new lease of life. If you’re considering changing your motor, see how you can sell your old one quickly and easily.
