Car trouble happens, and one of the most common issues is a dead battery.
It’s important you have the proper tools, equipment, and knowledge to help you get back on the road. Follow these eight easy steps to jump start your car safely and successfully.
What You Need to Jump Start a Car
Before getting to the steps themselves, you need to make sure you have the right equipment. Luckily, you don’t need much.
The most common way to jump start a car is by using jumper cables to connect the dead battery to a power source—either another car’s battery or a jumper box. These cables are thickly insulated with toothy clamps on one or two ends, and they are distinguished from each other by either their red or black color.
You will need two items to successfully jump start a dead car battery:
- Jumper cables
- A “donor”—a working vehicle with a compatible battery or a jump box
Jump boxes are used to start a car without connecting to the external battery of another vehicle, but the process involves the same steps.
Important Precautions to Keep in Mind When Jump Starting a Car
- Consult the manual. It’s always a good idea to consult the owner’s manual of the vehicle that needs jumping before you begin the process. The manual provides useful information such as the battery’s voltage.
- Match the voltage. Whether jumping a car from a jump box or another car’s battery, you need to make sure that the voltage of the donor matches the voltage of the dead battery.
- Don’t jump damaged batteries. If a dead battery is visibly damaged or corroded, do not try to jumpstart it: it will likely need to be replaced, and attempting to jump a damaged battery can be dangerous.
- Handle alligator clamps carefully. Through the jumping process, be aware of how you handle the alligator clamps on the jumper cables—do not let them touch each other.
8 Easy Steps for Jump Starting a Car Battery
Jumping a dead battery can be a safe and easy process so long as you follow these steps:
1. Get What You Need for the Jump
The first step in jump starting a car is making sure you have everything you need to complete the process. The two major things you need to jump a dead battery are some jumper cables and a donor source. It’s good practice to keep a pair of jumper cables in the trunk of your car at all times for this reason.
In most cases, you will jump a dead battery from another vehicle’s battery. Most cars use batteries with compatible voltage, so you can either find a friendly citizen or call a friend to give your car a jump. If all goes well, the process should only take them 15 minutes or so.
2. Prep the Vehicles
It is important that you properly prep and position the two vehicles for the jump. Typically, vehicles are positioned head-to-head so the jumper cables can easily connect to both cars’ batteries. Depending on your cable length, leave about 1.5 meters of space between the vehicles.
Once both vehicles are turned off completely and placed in the park position, apply the emergency parking brake on each. At this point, you can open the hoods of both cars and make sure they are securely supported in the open position.
3. Identify the Positive and Negative Components
Car batteries have two nubs on top. These are the battery’s terminals. Each terminal has its own charge—positive and negative—and will be marked accordingly. The positive terminal is commonly labeled with a “+” symbol or sometimes “POS.” Likewise, the negative terminal is labeled with a “-” symbol or “NEG.” Identify which is which for each car’s battery.
Jumper cables have two alligator clamps on each side, four in all. Similar to a battery, the alligator clamps each have either a positive or negative charge. The positive alligator clamp will be attached to the red cable and the negative alligator clamp to the black cable. When attaching the clamps, match the positive alligator clamp to the positive battery terminal and the negative alligator clamp to the negative battery terminal.
4. Attach the Alligator Clamps
Once you’ve identified the positive/negative terminals on each battery and the positive/negative clamps on the jumper cables, you’re ready to attach the cables to the car batteries.
It’s important that you attach the alligator clamps to the battery terminals in the following order:
- Red to Dead Positive: Attach one of the red alligator clamps to the positive terminal on the dead battery of the non-working car.
- Red to Donor Positive: Attach the opposite red clamp to the positive terminal of the donor vehicle’s working battery.
- Black to Donor Negative: Attach the black alligator clamp to the negative terminal on the donor car battery.
- Black to Metal Surface: Attach the other black alligator clamp to an unpainted metal surface on the non-working car. This will ground the cable as it transfers charge to the dead battery. Do not attach the clamp to the battery terminal.
5. Start the Donor Car
Now that the jumper cables are properly and securely in place, you can begin the charging process. This begins with the donor car. Start the car that is jumping the dead battery, being sure to leave the car in park and the emergency brake on.
Now that the donor car is running, leave it running for at least three minutes. At this point, the donor car is beginning to charge the dead battery, so there’s no need to do anything else while the donor car is idling. Leave the donor car’s engine running.
6. Start the Dead Car
After a few minutes of letting the donor car run, you can check the dead car’s charging progress. The best way to do so is by going into the car and trying to turn on the interior lights. You do not need to start the car to do this. If the lights turn on successfully, it is a good indicator that the dead battery is taking charge.
Once the lights turn on, you can try starting the car. While leaving it in park with the parking brake on, turn on the ignition in the jumped vehicle. When the car starts, you have successfully jump started the battery.
7. Remove the Alligator Clamps
Now that the car is running, it is safe to remove the alligator clamps and the jumper cables.
It’s important to do so in the opposite order you attached them:
- Remove the negative black clamp from the unpainted metal it’s clasped to on the jumped vehicle.
- Remove the other negative black clamp from the negative terminal of the donor vehicle battery.
- Remove the positive red clamp from the positive terminal on the donor car.
- Remove the final red clamp from the jumped vehicle battery.
Remember to remove the clamps cautiously, being careful not to touch any of the clamps together.
8. Keep the Car Running
After removing the jumper cables, be sure to leave the jumped car running continuously. Even though the car was able to turn on, the battery is not yet fully charged. Keep the engine running for the next 20 to 30 minutes to ensure it keeps and holds a full charge.
During this time, you can operate the vehicle as long as it is safe to do so. It is recommended to let it run by itself for at least 10 minutes before operating to confirm the battery is holding the charge.