How to Jump a Car

How To Jump A Car

Jumping a car battery is something that most drivers will have to do at some point. A dead battery is one of the most common issues for motorists, but it doesn’t have to leave you stranded. With a few simple steps and some basic equipment, you can get your car started again quickly and easily.

When You Need a Jump Start

There are a few signs that indicate your car battery needs a jump start:

  • The engine won’t turn over when you turn the key. You may hear a clicking sound or no noise at all.
  • The lights or dashboard electronics are very dim or don’t turn on at all.
  • The starter is slow and labored when you try to start the car.
  • You recently had a new battery installed but the car won’t start.

If your battery is more than 3 years old, it could simply be dying of old age. Extreme temperatures can also sap battery power. Frigid winter cold makes it harder for the battery to produce energy, while summer heat increases the rate of corrosion. Failing to drive your car for extended periods allows the battery to slowly discharge as well.

Gather the Necessary Equipment

Jump starting a car requires connecting good battery to the dead battery to transfer energy. You’ll need a few items:

  • Jumper cables – You need a set of jumper cables with sufficient length to comfortably reach between batteries. The cables should have insulated clamps at each end to attach securely to the battery terminals.
  • A car with a good battery – This car needs to be running to jump start your dead battery. The good battery must be the same voltage as your dead battery (in most passenger vehicles, this will be 12 volts).
  • Safety gear – Wear protective eyewear and gloves when handling jumper cables. Be aware of moving parts near the engine. Also, remove any metal jewelry that could conduct electricity.
  • A battery post cleaner (optional) – Having a wire battery brush makes it easier to clear corrosion from the battery terminals and ensure a good connection.

Before jumping the car, turn off all electronics like lights, radio, and cooling fans. Put both vehicles in Park and set the emergency brake.

Gather The Necessary Equipment
Gather the Necessary Equipment

Identify the Battery Terminals

Pop the hoods on both vehicles. Locate the batteries, which are usually under a plastic cover or in a metal battery box. You may have to remove a cap or access panel first.

Car batteries have a positive (+) and negative (-) terminal. The positive is typically larger in diameter. Most batteries are clearly labeled or color coded, with red indicating positive and black as negative.

Identify the corresponding terminals on each battery that you will connect: Positive to positive, and negative to negative. Never allow the jumper cables to touch each other while connected to the batteries.

Connect the Jumper Cables

With both vehicles turned off, make your cable connections in this sequence:

Attach the red positive (+) clamp to the dead battery’s positive terminal. Attach the other red positive (+) clamp to the good battery’s positive terminal. Attach one black negative (-) clamp to the good battery’s negative terminal.

Attach the last black negative (-) clamp to an unpainted metal surface on the disabled vehicle’s engine block. Avoid connecting it to the battery directly, which can cause sparks or engine damage.

Double check that the cables are securely attached and not touching each other. The final connection may cause a small spark at the last contact, which is normal.

Connect The Jumper Cables
Connect the Jumper Cables

Start the Working Vehicle

With the jumper cables in place, start the vehicle with the good battery. Let it idle for 2-3 minutes to partially charge the dead battery.

Attempt to start the car with the dead battery. If it doesn’t start right away, make sure the cable connections are secure. Let the working car idle for a few more minutes to send more juice to the dead battery.

If the dead battery is very low, you may need to wait 10 minutes or longer before trying again. Continue to let the working vehicle idle during this time.

Remove the Jumper Cables

Once the dead car is running, remove the cables in reverse order:

  • Disconnect the black negative cable from the vehicle’s engine block.
  • Disconnect the black negative cable from the good battery.
  • Remove the red positive cable from the good battery.
  • Remove the red positive cable from the revived battery.

With the cables removed, let the jumped car continue to run for at least 15-20 minutes. This allows the battery to recharge further while on the road. Avoid turning it off right away until the battery has had time to partially recharge.

Remove The Jumper Cables
Remove the Jumper Cables

What to Do After a Jump Start

Here are a few key steps to take right after a successful jump start:

  • Let the car idle for 15+ minutes before turning it off to allow the battery to recharge.
  • Drive the car for 20-30 minutes to fully recharge the battery via the alternator.
  • Check and clean any corroded battery connections.
  • Have the battery tested as it may need replacement soon.
  • Address any electrical issues that could be draining the battery.

With some care immediately after a jump, you can help ensure your car keeps running and minimize the chances of another dead battery. But a battery nearing the end of its lifespan will need replacement.

Safety Tips for Jumping a Car

  • Use adequate, well-insulated jumper cables.
  • Confirm cable connections to proper battery terminals.
  • Avoid sparks by connecting to engine block, not battery.
  • Wear protective gear like gloves and eyewear.
  • Do not allow cable clamps to touch while attached.
  • Keep clear of moving engine parts.
  • Avoid getting battery acid on skin or eyes.
  • Do not jump start a frozen battery.
  • No smoking near batteries.
  • Check battery’s age and condition.

By following safety precautions, you can easily get your car up and running after a dead battery. With the right equipment and some basic know-how, jump starting a car is a simple fix.

Safety Tips For Jumping A Car
Safety Tips for Jumping a Car

Using a Portable Jump Starter

Portable jump starters provide an all-in-one solution for jump starting a dead battery without requiring a second vehicle. They contain an internal battery that can be charged from a wall outlet and used to provide a powerful boost when needed.

To use a portable jump starter:

  • Fully charge the internal battery per the manufacturer’s instructions. Check charge level before use. Connect the positive and negative clamps to the proper battery terminals just like jumper cables.
  • Turn the jump starter on and allow it to charge the dead battery for a few minutes before attempting to start the car.
  • Disconnect the jump starter once the car is running. Drive for 15-20 minutes to recharge the battery.

Advantages of portable jump starters:

  • No second vehicle required.
  • Compact size stores easily in your trunk or glovebox.
  • Provides multiple jumps on a single charge.
  • Some models can charge phones and other USB devices.
  • Safer than jumper cables since they don’t require touching a running engine.

When purchasing, look for a reputable brand with at least 400 amps of peak current. Compare battery capacity and number of jump starts per charge. Units with built-in battery chargers and LED flashlights can also come in handy.

Signs Your Battery Needs Replacement

If your car battery is more than 3-5 years old, watch for these signs it may need replacement soon:

  • Fails to start the car, especially in cold weather.
  • Dimming or flickering lights when engine is off.
  • Corroded or loose battery connections.
  • Cracks, leaks or bulging of the battery case.
  • Needs frequent jump starts even with regular driving.
  • Battery tester shows low charge and high internal resistance.

Continuing to recharge an old or damaged battery will provide diminishing returns. Have your battery tested at an auto parts store if you notice any of the above signs. Replacements can typically be installed in under an hour.

Select a new battery with the same group size, voltage (normally 12V), and cold cranking amps (CCA) rating as your old one. The CCA number indicates how much power the battery can provide to start a cold engine. A higher CCA rating may be needed for vehicles in colder climates.

Maintaining Your Car’s Battery

Simple maintenance can maximize your car battery’s lifespan and performance. Try these battery care tips:

Keep the battery secured in place to minimize vibration damage. Clean any corrosion from battery terminals using a wire brush and battery cleaner spray. Re-tighten lugs if they become loose to ensure a solid connection. Check that vent tubes are clear of debris and function properly.

Neutralize small leaks or acid build up using a baking soda/water paste. Rinse well. Avoid disconnecting or removing the battery unnecessarily. Let your vehicle run for 20-30 mins once a week if driven infrequently.

Periodically inspect your battery’s charge level and connections. Catching minor issues early on can help avoid being stranded with a dead battery.

Here are some frequently asked questions I can add about jumping a car battery:

Frequently Asked Questions

How long does a jump start take?

With the proper jumper cables and a good battery, a jump start usually takes 5-10 minutes. Allow the working car to idle and charge the dead battery for 3-5 minutes before trying to start. Give it 10+ minutes of charging time if the battery is very depleted.

What if my car won’t start after a jump?

If the jumped car doesn’t start right away, double check the cable connections to ensure they are tight on the correct battery terminals. Let the working car run for 5 more minutes to provide additional charging time. The battery may need a longer jump start if it was completely dead.

Can I damage my car by jump starting it incorrectly?

Yes, incorrect connections can damage electrical systems in your vehicle. Attaching the jumper cables incorrectly can cause sparks or even an explosion. Never connect the last cable to the dead car’s battery – only to its metal frame. Avoid sparks and reversed polarity at all costs.

How many times can you jump the same car before needing a new battery?

There’s no fixed number, but if your battery is dying repeatedly under normal driving conditions, then it likely needs to be tested and replaced. Most batteries last 3-5 years. Frequent jump starts indicate the battery can no longer hold a full charge.

What should I do after a jump start?

Drive for 15-20 minutes to allow the alternator to recharge the battery. Then have the battery tested at an auto parts store to see if it’s still holding a proper charge or needs replacement. Tighten any loose connections and clean corrosion as well.

Can I disconnect the battery while the car is running?

No, never disconnect a battery while the engine is on. This can send a damaging voltage spike through your vehicle’s electrical system. Always turn off the engine before disconnecting or removing a battery from the car.

Is it safe to jump start a car in the rain?

Yes, it’s fine to jump start in wet conditions – just take extra precautions. Keep the jumper cables away from puddles and any wet engine components. Make sure your hands are dry when making connections. Avoid leaning directly over the batteries as well.


Jump starting a car is one of the most common roadside repairs faced by drivers. But armed with the proper gear and knowledge, it doesn’t have to lead to a stranded situation. Keeping jumper cables and a portable jump starter in your vehicle provides

the tools you need for a quick battery boost. Taking a few minutes to correctly connect the batteries and allow adequate charging time can get your car back on the road. Knowing the warning signs of a failing car battery helps avoid being caught off guard at the worst moment.

Dimming headlights, slow cranking, and frequent jump start needs all indicate a battery may need testing or replacement soon. Proper maintenance and care extends the life of your vehicle’s battery as well. While a dead battery can certainly be an inconvenience,

a jump start is a relatively simple fix. Following some basic safety guidelines reduces any risk of sparks or damage too. Don’t let a depleted battery leave you stranded – keep your car ready to hit the road with the tools and knowledge for a successful jump start.

Related posts

Leave a Comment