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How to jump start a car, in the right order

Updated October 8, 2026

Red goes on first, starting with the dead battery. The last black clamp goes on bare metal on the dead car, not on its battery.

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Before you connect anything

  • Park the two cars close, but not touching.
  • Turn both cars off. Set the parking brakes.
  • Look at the dead battery. If the case is cracked, swollen or leaking, stop. Do not jump it.
  • Drive a hybrid or an electric car? Read the owner's manual first. The steps and the jump points can be different, and some makers say not to use their cars to jump another one.

Which jumper cable goes on first

Diagram of jumper cable order. One: red clamp on the dead battery positive post. Two: red clamp on the good battery positive post. Three: black clamp on the good battery negative post. Four: black clamp on bare metal on the dead car.
The last black clamp goes on bare metal, away from the dead battery.
  1. Red to dead. Clamp one red end on the positive post of the dead battery. Positive is marked with a plus sign.
  2. Red to good. Clamp the other red end on the positive post of the good battery.
  3. Black to good. Clamp one black end on the negative post of the good battery.
  4. Black to bare metal. Clamp the last black end on a clean, unpainted metal part of the dead car, like a bolt on the engine. Not the dead battery's negative post.

Why the last clamp goes on metal: that last connection can make a small spark. A battery can give off gas that burns. Putting the clamp away from the battery keeps the spark away from the gas.

Start the cars

  1. Start the car with the good battery and let it run for a few minutes.
  2. Try to start the dead car.
  3. If it starts, take the cables off in the reverse order. Black from the metal first, red from the once-dead battery last. Do not let the clamps touch each other.

How long to drive after a jump

Keep the engine running for at least 30 minutes. A short trip around the block will not put enough charge back. Then have the battery charged and tested. A battery that went dead once will often do it again.

Jump starting without another car

A portable jump pack does the same job with no second car. The cable order is the same. Follow the directions that came with the pack. One tip from AAA: do not store a jump pack in a hot car.

If the jump does not work

  • It clicks but will not turn over. Check that the clamps are biting clean metal, wait a few more minutes, and try once more.
  • It starts, then dies within 10 to 15 minutes. That points to the alternator, not the battery.
  • The dash lights up but the engine does nothing. That can be the starter.

Our guide on why a car will not start walks through each one. And if you would rather not do this on the side of the road, call for a jump.

Where these facts come from

Checked on October 8, 2026.

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