A dead car battery is one of the most common reasons why a car won’t start. If you find yourself in this situation, you may be able to use jumper cables to jump start your car from another vehicle with a working battery. Follow these steps to jump start your car safely

Firstly, how do you know if you need to jump-start it? If any of the following things are happening, you probably need to jump start your battery. 

  • Loss of power to car/electrics 

If you’re turning your key in the ignition and nothing is happening, it probably means your battery is dead. This is also the case if none of your car electricals are working (headlights, radio, AC). 

  • Cranking the engine  

Another common battery-related problem is when the engine cranks as you turn the key in the ignition, but it refuses to start. The engine will make a chugging sound as you try to get your car started, but you’ll be unable to actually turn the engine on. 

  • On and Off again  

One day your engine is running smoothly, the next it won’t start. If you’re having ongoing problems that make your car unreliable, it will mean that either your battery terminals are loose, broken, corroded, or calcified or that you have a parasitic draw. Which means you’ll need to jump start you car or call a mechanic.  

What You’ll Need  

  1. Jumper cables  
  1. Another vehicle with a working battery  
  1. Gloves (optional) 

Safety Tips  

  • Make sure both vehicles are turned off and that their keys are not in the ignition  
  • Park the vehicle with the working battery close to the hood of the disabled vehicle, but do not let the cars touch  
  • Put on gloves if you have them 
Cartoon image of a red car charging with a green car on a blue background. Both cars have batteries on top that are connected to each other.

How to jump start your car:

  1. Clamp one end of the red jumper cable to the positive terminal of the dead battery  
  2. Clamp the other end of the red jumper cable to the positive terminal of the working battery  
  3. Clamp one end of the black jumper cable to the negative terminal of the working battery  
  4. Find a bare metal surface on the disabled vehicle that is not near the battery, such as a bolt on the engine block  
  5. Clamp the other end of the black jumper cable to this bare metal surface  
  6. Start the vehicle with the working battery, and let it run for a few minutes  
  7. Try starting up your disabled vehicle. If it doesn’t work, check all of your connections to make sure they’re secure and try again. 

How long does it take to jump-start a car?  

Once the cables are connected, jumpstarting your car should only take a few minutes. Between 5 to 30 minutes depending on conditions. To fully recharge the battery, you must drive for at least 15 minutes after restarting the vehicle.  

What happens when you jump start a car the wrong way? 

Each car is different, but each has fuses that help protect the car. If an accident does occur, most of the time you don’t need to be concerned for your safety. The car may sustain a little damage, but nothing serious usually occurs that would lead to serious harm. 

The damage will depend on how long you try to jump it in the wrong way, the components and battery will take more damage the longer the cables are in the wrong place. There may be sparks or the cables may start to burn or melt. If corrected quickly (by turning both engines off and leaving for a minute) there will be minute damage. 

How many times should I jump my battery? 

If the issue persists and you have to jump the car more than once within a few uses, it may need to be looked at by a qualified car mechanic, as the problems may have escalated past the battery dying. It’s best to call someone as soon as this problem happens more than once. 

What if the jump-start doesn’t work?  

If the car doesn’t start on the first try, wait a few minutes, and try again. Similarly, if the issue happens more than once,  your vehicle may need to be looked at by a qualified car mechanic. It’s best to call for assistance if you are unsure of the reason your car will not start. 


Jump starting a car is a pretty easy process that anyone can do with just a few supplies and some knowledge of what they’re doing. Once you’ve jump started your car, be sure to drive around for at least 15 minutes so that your battery can recharge itself. If you have any doubts about your ability to jump start your car, or if you don’t feel comfortable doing it, call a maintenance truck or AA and they will be able to help you out. Just remember to be careful when connecting the jumper cables and make sure to follow these steps exactly in order avoid any accidents or injuries!