How to jump start a dead car battery


If you can tell red from black, you can jump start a dead battery. Car expert Lauren Fix shows you how it's done.

How to jump start a dead car battery
  • To jump start a dead battery, you will need a second car with a live battery. Pull the two cars as close together as possible, making sure the cars do not touch.  Turn off the engines, remove the keys, engage the emergency breaks and open the hoods on both cars.
  • Start with a set of jumper cables. Each end of the jumper cable has two clamps - one red (positive) and one black (negative).  An easy way to remember is to think about the color red (positive) as "hot" or "spicy" or "full of energy"  and black (negative) like the ground.
  • With the engine off, attach the red (positive) clamp to the red (positive) battery post on the live car's battery. Then attach the black (negative) clamp to the black (negative) post on the live car's battery.  
  • Attach the red (positive) clamp to the red (positive) battery post on the dead car's battery.
  • Next, attach the black (negative) clamp to a piece of metal - it can be part of the frame. Do not connect it to the car's black (negative) battery post.
  • Start the engine of the live car, followed by the engine of the dead car.
  • Let both cars idle for a few minutes to allow enough energy to flow to the dead battery.
  • Disconnect the cars beginning with the live car.  Disconnect the black (negative) cable first and then the red (positive) cable.  DO NOT LET THE ENDS OF RED AND BLACK JUMPER CABLES TOUCH.
  • Disconnect the jumper cables from the other car. 

Important Tips:

  • Always consult the owner's manual of a car before jump starting a dead battery.
  • The voltage from a car battery is dangerous, whether the engine is running or not. Do not touch the metal ends of the cables with your hands or touch them to each other.

I'm Lauren Fix, the Car Coach, for Have you ever had a dead battery on your car? It can be very frustrating. I'm going to show you how to jump a car safely.

Let's first start off with a set of jumper cables. There are two ends that are exactly the same: two red and two black. Now how do you know the difference?Red is for positive, which is a positive on the battery. How do you remember that from negative which is black? Here's a simple way to remember: red, think of salsa or hot sauce and positive where the energy comes from, and black is negative like the ground. Again that's the negative and the positive on the battery.

The first thing you want to do is take the red end, the positive, and attach it to the positive end of the cable on your battery. So you want to squeeze the clamp, attach it to the positive, then take the negative and attach it to the negative.

Now it doesn't make a difference which car you connect first, just do it one at a time, and make the sure the positive and the negative are correct. Attach it to the battery if you have any doubt. 

Now let's go to the vehicle that has the dead battery. Now the secret to your safety is to not have these two ends touch once the other end of the jumper cable is attached to the battery. That could actually shock you. Now let's connect the red, or the hot, to the red or positive battery post, and the negative does not go to the negative battery post, it goes to some raw metal. It could be the frame, it could be a bolt, it could be a clamp.

Now, it's attached to the metal and you can start the good car followed by the car with the dead battery.  Let them idle for just a few minutes so you can add a little bit of energy to the battery that was dead. Now that both vehicles are started, disconnect the good vehicle. Make sure not to let the battery jumper cables touch. Starting with the negative, then the positive. Now let's disconnect the cable from the car that had the dead battery.

Now you're ready to hit the road. I'm Lauren Fix, the Car Coach, with 


meet theexpert
  • Lauren Fix

    Lauren Fix The Car Coach, Automotive Expert Lauren Fix, the Car Coach® is America's Award winning automotive expert and the leading female automotive expert in the industry. She is ASE certified, a SAE member and has worked in the automotive industry all her life. more about this expert »

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