How to Jump-Start a Car

Last updated September 7, 2023
Jump-starting your car involves using the battery of another vehicle to crank up your engine. If your car is making a startup noise when you turn the key in the ignition but does not fully engage, the battery may need an extra boost. This guide will provide step-by-step instructions on how to jump-start a car.
Difficulty:
Beginner
Duration:
Under 2 hours
Table of Contents
Locate Another Vehicle
Locate the Battery Terminals
Connect the Jumper Cables
Jump-Start the Car
Remove the Jumper Cables
Locate Another Vehicle

- In order to jump-start your car, park another vehicle with a full battery near your car.
- To make sure the jumper cables reach, park the second car in front of the one with the dead battery so that both front bumpers are facing each other.
- If there’s not enough space to park with the front bumpers facing each other, park the other vehicle closely alongside your car so the car batteries are as close together as possible.
Tip: Although both vehicls should be close together, they should not be directly touching each other.
Locate the Battery Terminals

- Take the keys out of the ignition in both vehicles and open the front hoods.
- Find both batteries and locate the positive and negative terminals on each one.
- Car batteries have two metal terminals. The positive terminal will be marked with a plus sign (+) and the negative terminal will be marked with a minus sign (-). If there is no symbol indicator, the positive terminal will be connect with a red cable and the negative terminal will be connected with a black cable.
- When using the jumper cables, remember that the red clamp connects to the positive (+) terminal and the black clamp connects to the negative (-) terminal.
Connect the Jumper Cables

- Separate the jumper cables. Make sure the ends do not touch each other throughout the jump-start process.
- Take one end of the jumper cables and connect the red clamp to metal post on the positive terminal of the dead car battery. Set the corresponding black clamp to the side.
- Move to the other end of the jumper cables and connect the red clamp to the metal post on the positive terminal of the chargedcharged car battery.
- Connect the corresponding black clamp to the metal post on the negative terminal of the charged car battery.
- Go back to the dead car battery and find a grounding piece of metal to attach the final black clamp. Do not attach the black clamp to the negative terminal on the dead car battery as this can cause electrical sparks and poses a safety hazard.
- Some cars have a built-in grounding spot under the hood for this task. Read your car's owner’s manual for more details.
Tip: To make sure the cables are well connected, make sure the metal pieces on each clamp are touching the metal part of each battery terminal post.
Jump-Start the Car

- Once the cables are connected, start the vehicle with the charged battery and let it run for a couple minutes.
- Go to the car with the dead battery and turn the key until the engine fully starts. It may take a few moments for the dead battery to pull energy from the other vehicle.
Remove the Jumper Cables

- Leave both cars running.
- Start with the car that has the dead car battery and remove the black clamp from its grounding spot. Set it on the ground nearby, making sure it does not touch anything else under the car hood.
- Remove the red clamp from the positive terminal on the dead car battery. Set it on the ground next to the black clamp and make sure they don’t touch each other.
- Move over to the car with the charged car battery and repeat the process.
- Remove the black clamp from the negative terminal and set it on the ground nearby, making sure it does not touch anything else under the car hood.
- Remove the red clamp from the positive terminal and set it on the ground.
- Once all clamps have been removed, you can roll up the jumper cables and put them away.
When you know how to jump-start a car, you can help yourself or others having trouble on the road. Keep jumper cables in your car so you’re prepared if your car has a dead battery.
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