How to Jump-Start a Car Safely, Step by Step

A jump-start can get you moving, but it does not fix a battery that is failing. If a jump works, get the battery tested soon, because the same thing will probably happen again.

Before you start

• Check your owner's manual. Some vehicles have specific jump points under the hood, and hybrids and EVs often have special instructions.
• Do not jump a battery that is cracked, leaking, bulging or frozen.
• Wear eye protection if you have it, and keep sparks, flames and cigarettes away from the battery.
• Make sure both vehicles are off, in park or neutral with the parking brake on, and that the two cars are not touching.

The steps

1. Connect one red clamp to the positive (+) terminal of the dead battery.
2. Connect the other red clamp to the positive (+) terminal of the good battery.
3. Connect one black clamp to the negative (−) terminal of the good battery.
4. Connect the last black clamp to bare, unpainted metal on the dead car's engine or frame, away from the battery. This is your ground. Connecting it to the dead battery's negative terminal can create a spark right next to the battery.
5. Start the good car and let it run for a few minutes.
6. Try to start the dead car. If it does not start, wait a couple of minutes and try again.
7. Once it is running, remove the clamps in reverse order, starting with the black clamp on bare metal. Do not let the clamps touch each other.

After the jump

Keep the car running and drive it for a while so the alternator can recharge the battery. If the car will not restart later, or dies shortly after the cables come off, the problem is the battery or the alternator, and it is time to have it checked.