How to Jump-Start a Car
If your car won't start but seemed fine the last time you drove it, it's likely that the battery is flat. In a petrol or diesel car, the battery is used to start the engine, and is charged up whenever you drive. A car with a flat battery can get going using a jump-start, and its battery will be recharged once it gets going. Check out these instructions for how to jump-start a car, quickly and simply.
Things you’ll need
There are a few things you’ll need to jump-start a car:
- Another car with a charged battery
- 2x jump leads: one red (positive) and one black (negative) lead
- Additional safety equipment such as gloves or goggles
Get set up to jump-start a car using these steps:
- Park the car with the working battery so its bonnet is facing the bonnet of the car with the flat battery
- Make sure there’s enough space between the cars to open both bonnets
- Put both cars in neutral and check that their handbrakes/parking brakes are applied
- Open the bonnets of both cars
- Locate the batteries of both cars. These should be marked, but may have covers on.
2. Charge up the flat battery
To jump-start a car, you’ll first need to charge up the flat battery.
- Put on any safety kit
- Attach one end of the red jump lead to the positive (marked “+”) terminal of the battery in the car with the charged battery
- Connect the other end of the red jump lead to the positive terminal of the flat battery
- Attach one end of the black jump lead to the negative (marked “-“) terminal of the battery in the working car
- Connect the other end of the black jump lead to a piece of solid metal on the car with the flat battery, away from the battery and fuel system of both cars. Some cars have an “earthing rod” part for this purpose – check the manual if you’re unsure
- Wait five minutes
3. Start the car with the flat battery
Once you’ve connected up the jump leads and waited five minutes for the flat battery to gain some charge, you’re ready to move on to the next steps:
- Start the engine of the working car (make sure it’s in neutral with the handbrake on)
- Leave the engine of the working car running for a couple of minutes
- Try starting the engine of the car with the flat battery
- If it doesn’t start within five minutes, wait for a few more minutes before trying again
Once both cars have started, leave them parked with the engines running for ten minutes. Then, remove the jump leads in the following order, taking care not to let the clamps touch one another or any metal.
- Remove the black lead from the car with the flat battery
- Remove the black lead from the car with the charged battery
- Remove the red jump lead from both cars
4. Keeping the car battery charged
Once the car with the flat battery has started, you’ll need to charge the battery. To do this, run the engine for at least half an hour (either static or by driving the car). This should fully charge the battery.
If your car needs jump-starting frequently, it may be due to the following causes:
- Leaving the headlights or internal lights/radio/heat on for long periods without the engine running
- Only taking the car on very short trips so the battery doesn’t have the chance to fully recharge
- Cold or wet weather can drain the battery
- An old or worn battery may lose charge more quickly
If a car needs to be jump-started often, get the battery checked as it may need to be replaced. You can also get portable battery packs for situations where there is not another car available for jump-starting – follow the manufacturer’s instructions on these.
A flat battery doesn’t have to stop you going places – a jump-start will get the car back on the road in no time. If you often need to jump-start a car, consider getting the battery checked, as they can lose their charge capacity with age.