Beginner10 min2 tools

Jump Start a Dead Battery

A dead battery is one of the most common car problems — and one of the easiest to solve if you know what you're doing. This guide walks you through a safe jump start step by step.

Step-by-step instructions

  1. 1

    Position the vehicles

    Park the working vehicle so the two batteries are close enough for the jumper cables to reach — usually nose-to-nose or side-by-side. Turn off both vehicles.

    The vehicles don't need to be touching. A foot or two of space is fine.

  2. 2

    Identify the battery terminals

    Each battery has two terminals: positive (+) marked in red, and negative (-) marked in black. Make sure you can clearly identify both on each battery before you touch anything.

    If the terminals are corroded (white or blue-green buildup), that may be why the battery died. Clean them with a wire brush if you have one.

  3. 3

    Connect the cables in the right order

    This order matters: (1) Red clamp to dead battery positive. (2) Red clamp to good battery positive. (3) Black clamp to good battery negative. (4) Black clamp to an unpainted metal surface on the dead car's engine — NOT the dead battery's negative terminal. This reduces spark risk near the battery.

    Say it out loud as you connect: red-dead, red-good, black-good, black-metal.

  4. 4

    Start the working car

    Start the working vehicle and let it run for 2–3 minutes. This charges the dead battery slightly before you try to start the other car.

    Rev the engine gently to 1,500–2,000 RPM to push more charge into the dead battery.

  5. 5

    Start the dead car

    Try to start the car with the dead battery. If it doesn't start, wait another 2–3 minutes and try again. If it still doesn't start after a few attempts, the battery may be too far gone or there may be another issue.

    If the car starts but dies again immediately, the battery likely needs to be replaced, not just jumped.

  6. 6

    Disconnect in reverse order

    Remove the cables in the reverse order you connected them: (1) Black from engine metal. (2) Black from good battery. (3) Red from good battery. (4) Red from jumped battery.

    Keep the jumped car running for at least 20–30 minutes to let the alternator recharge the battery.

  7. 7

    Get the battery tested

    A battery that died once may be fine. A battery that keeps dying needs to be replaced. Any auto parts store will test your battery for free.

    Car batteries typically last 3–5 years. If yours is older than that, consider replacing it proactively.

You did it.

Jump starting a car sounds scary the first time. Once you've done it, it's just a 5-minute task.