How To Jump A Car Battery Safely And Properly


There are few worse feelings than that moment when you turn the key to your car and realize that the battery is dead. This can happen in 100 degree heat or below freezing temperatures, late at night or in a remote location. Being stranded with a dead battery can be a scary and even dangerous situation.

This is why it’s absolutely essential that you know how to properly jump start a car. Knowing how to safely and correctly jump a car can be the difference between an anxious few minutes and a completely ruined day.

So what do you do when you need to jump start your car? First of all, you need to be prepared ahead of time with the right tools for the job. Second, you need to be able to follow the steps needed to use one of the two methods for how to jump a car.

Related: What Size Jump Starter Do I Need?

What You Need

There are two basic ways to jump a car, each requiring different tools and a different (though similar) technique. Each has pluses and minuses, and you’ll want to choose the one that seems best suited to you.

Jumper Cables

The first method of how to jump a car is by using jumper cables to link your dead car battery to the charged car battery of another automobile. The charged battery will provide the initial power needed to get your dead battery running again.

This way of jumping a car requires that you have jumper cables stored in your car in case of emergency. If you don’t have jumper cables, you can hope that a good Samaritan has cables and is willing to help you out.

However, it’s much better to be prepared so that you’re not reliant on another person providing the cables.The downside to using jumper cables to jump your car is that you need another automobile, which means either calling a friend, relative or acquaintance to come to you, or relying on a stranger to help you.

If you’re somewhere by yourself, such as a parking garage in the middle of the night, help might not be so easy to come by.

Related: Top 7: Best Deep Cycle Battery Charger Reviews (For Cars)

Portable Car Jump Starter

The other way to jump start a car is to use a portable car jump starter. These devices are essentially a battery that can be charged via a wall socket, which you then carry with you. As long as the charge holds, you’ll be able to use it to jump your car without help from another automobile.

These devices are compact, easily able to fit in a glove box or beneath a seat. The only downside to a portable jump starter is that you must make sure to keep it charged, otherwise you’re out of luck.

Most devices will hold a charge for weeks at the least, but if you forget and don’t charge it for a year, when the time comes to jump a car the battery won’t be able to jump it.

Which to Choose?

If you are the type of person who is confident in your ability to remember to keep a portable car jump starter charged, then this is the best option of the two.

What’s great about a portable jump charger is that you’re not reliant on another person. This is especially key if you tend to travel in rural or wilderness areas.

If you tend to be a bit on the forgetful side at times, jumper cables are the safer bet. They’ll always work, provided you can find a charged car battery to hook them onto.

Related: Top 10: What is The Best Lithium Jumpstarter on the Market

Step-By-Step Instructions

First, we’ll cover how to jump a car with jumper cables.

1. Position the Other Automobile

The first thing you’ll need to do is position the other car in relation to your car. Park the car with the working battery so that your cars face each other, leaving about two feet distance between the two.

The cars should never touch one another. If it’s a situation where you’re parking against a wall or obstacle, you can park the cars side by side, and the cables should be long enough to reach.

2. Prepare Both Automobiles

Each car should be put in park if an automatic transmission and neutral if a manual transmission. For both cars, engage the parking brake so that neither car is able to move unexpectedly during the process. Both cars should be shut off, with the keys removed.

Lift the hoods of both cars and locate the batteries. If you’re not sure where either battery is, the owner’s manual will be able to guide you to the right location.

Place the jumper cable on the ground, making sure that none of the clamps are touching one another.

Related: Top 10: Best Trickle Charger For Car Batteries And Motorcycles

3. Attach the Jumper Cables

Each battery will have two terminals, a positive and a negative. Positive will usually be covered or marked with red, and negative with black. Make sure that you’ve identified which of the terminals is positive and which is negative for both batteries.

Pro Tip: If the terminals of either battery appear to be dirty, wipe them off with a wire brush or rag.

Attach the red, positive clamp of the jumper cable to the positive terminal of the dead battery. Then, attach the other red clamp of the jumper cable to the positive terminal of the live battery.

Next, connect the black, negative clamp of the jumper cable to the negative terminal of the dead battery.

Last, do NOT clamp the final jumper clamp to the negative terminal of the functioning car’s battery. Instead, clamp it onto an unpainted metal part of that car. A clean nut on the engine block would be a good example of something you could use.

4. Start Up the Working Car

Start up the car with the functioning battery, leaving that car in park (if automatic) or neutral (if manual). Let the car run for at least a minute or two before doing anything with your car with the dead battery.

Depending on the age and charge of the batteries in question, you might need to let the working car run for more like four to five minutes. Another technique that can help is lightly revving the engine of the functioning car during the process.

5. Attempt to Start Up Your Car

While the working car is still running, attempt to start up your car. If the car doesn’t immediately start, give the working car an additional couple of minutes to continue to charge its battery and try again. Rev the engine of the working car as you attempt to start up your car.

6. Remove the Jumper Cables

Assuming that your car is now running, remove the jumper cables. Begin by removing the black, negative jumper clamps. Make very sure not to touch the clamps to one another while any of the cables are still attached to or touching the car.

Pro-Tip: During the entire jumping process, make sure that children are in a safe place and accounted for, so that there’s no risk of them touching a cable bearing a live charge. It’s crucial to know how to safely jump a car.

Related: Top 10: The Best Jumper Cables Review

7. Take a Drive

Once you’ve jumped your dead battery, you’ll want to drive it around for a while to make sure that it retains its charge. It’s advisable to drive for at least 15 minutes, to let the alternator charge up the battery fully.

If you shut the vehicle off too soon after jumping it, it’s possible that you’ll find that the battery will once again be dead when you try to start it the next time.

If you drive it around for a sufficient length of time and still find that the battery keeps dying each time you shut it off, it’s likely that the battery can no longer hold a charge, and must be replaced.

Now, we’ll cover how to jump a car using a portable car jump starter.

The first big difference is obvious: There’s no other car to worry about. All you’ll be dealing with is your own car and the portable starter.

Prepare the Car and Charger

Very similarly to with a jumper cable, open your hood and locate the battery. A portable jump starter will have a set of red and black clamps just like jumper cables, and you’ll want to attach the red clamp to positive, black to negative.

Attempt to Start Your Car

Once the portable starter’s cables are attached, attempt to start up your car. Unlike with jumper cables, there really aren’t many tricks at your disposal if the car doesn’t initially start. If there’s not enough charge in the portable charger, the car may not start. If you’ve got sufficient power, it should start right up.

Take a Drive

Once the car is running, remove the clamps on the portable charger and secure the device, then take the car for that same drive of at least 15 minutes to ensure it holds a charge.

Related: Top 15: What is The Best Digital Multimeter for your Diagnostic Needs?


I hope you enjoyed this tutorial on how to jump start a car. More than that, I hope it gave you the skills and knowledge you need to be prepared for a situation where your battery is unexpectedly dead.

We often take our cars for granted, right up until the moment when they stop working. Having a plan for getting I encourage you to give your own thoughts and feedback in the comments, and hope you’ll share this article if you liked it and found it useful for anyone who needs to know how to jump start a car.

(No Ratings Yet)


The newest gear, techniques, & advice delivered to your inbox.

Latest in How To