Dead Battery? How to Jump Start Your Vehicle

It's been a busy day, and the last thing you want before you head home is a car that won’t start. The good news is that with some basic equipment and the knowledge we're about to provide, you can jump-start your car quickly!

Find the Battery

Usually, the battery sits in the engine compartment under the hood. It may also be located in the trunk or under the rear seat though. If you still are having a hard time finding it, check your owner’s manual. If you're having a hard time finding the owners manual there's no need to worry. Even if the battery is in a hard-to-find spot, it’s usually wired to the engine compartment to support jump-starting conveniently from under the hood.


Although it's super rare, batteries can actually rupture and leak acid. Incorrectly connected jumper cables can create sparks. For this reason, we recommend having eye and hand protection. If it's a battery that’s been dead for a while, it’s best to seek professional assistance like the team at Finch Used Cars, just to be safe.

Grab the Proper Equipment

If your vehicle does has electrical power, won't start, you’ll hear a click when you turn the key and some lights will probably still turn on. This means the battery still has some power, but not enough to start the engine. If this happens, thin jumper cables and a small battery jump-pack or battery booster should be enough.

If your power door locks, windows, and interior lights aren't working that means your battery is completely dead. If that happens you will need to supply all the power from another power source, meaning you will need thick jumper cables that can carry more current (3/8 inches in diameter or more) or a large battery jump-pack.

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4 Steps to Connect the Cables

Connecting your car to a power source, no matter if it's a battery pack or another car, is not hard. However, it is important to connect the cables in the following order for your safety:

1. To jump-start a dead battery from another vehicle, first make sure the other vehicle is turned off, and then connect the jumper cables to the car receiving the jump. First you need to identify the positive terminal or connection point under the hood. The best way to know you have found the positive terminal is to look for the “+” embossed on the actual battery, usually under a red cover. Clip one of the positive red clamps to the positive terminal.

2. Next, connect the other red clamp to the positive terminal of the car providing the jump, followed by the negative black clamp to the negative terminal of the car providing the jump. Finally, to ensure a grounded connection and avoid damaging the battery, attach the final negative clamp (located next to the positive clamp) to a sizable metallic component of the engine. NOT the negative terminal of the battery. Make sure you don't clamp to thin sheet metal, painted surfaces, or fluid-bearing tubes. Also be careful to avoid areas around the belts of the engine and the cooling fans.

3.After the first 2 steps, start the engine of the car providing the jump and, after letting it run for a few minutes, attempt to start the car with the dead battery. The car may crank slowly, but the goal is to let the battery charge so that you can get the engine to start. If the engine does not start, turn off both cars, check the connections, adjust the clamps to make sure you have full contact, and restart the engine of the car providing the jump, followed by the car with the dead battery. If the car still does not start, leave the cables connected and let the running vehicle “charge” the dead battery for 10 to 15 minutes before trying to start the dead car again.

4. Once the car with the dead battery is running, carefully disconnect the connection with the grounded negative clamp on the car that provided the jump first. From there, disconnect the negative clamp from the car that received the jump, followed by the positive cables in whichever sequence is most convenient. Be careful to keep the jump leads and clamps away from rotating components of the now running engine. Also, it’s a good idea to keep the newly re-charged battery in use for 30 minutes before turning off the engine in order to ensure the charge holds. If the battery is nearing the end of its life (usually around 6 years), it may need to be replaced by a mechanic.

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The Bottom Line

With a little preparation, you can jump-start your car in the same time to read this article. The key is being ready, and knowing what to do. That’s why we recommend keeping a set of thick, high-quality jumper cables capable of starting a fully dead battery in your vehicle at all times.