How to Jump Start a Car
There may be a time when you need to jump start your car or someone else’s car. Jump starting a car is pretty easy. The most important thing is to do it safely.
What You Should Never Do:
- Never lean over a car battery.
- Never smoke or use a cell phone while doing a jump start.
- Never jump start a car if the battery is cracked or visibly leaking.
- Never jump start a car battery if the fluids are frozen.
What You Need:
- Jumper cables with thick wires and clean, rust-free clamps.
- Another car with a battery the same voltage as your own.
- Rubber gloves.
- A wire brush.
- Check your owner’s manual. Some new cars have jump start lugs to attach jumper cables to rather than directly to the car battery terminals. Some cars prohibit jump starting altogether. If you’re not sure, don’t jump start your car and call a professional.
- Park the cars so the batteries are close to each other, but not touching.
- Turn off the engine of the car with the live battery.
- Unplug all accessories from both cars. The power surge could short the equipment.
- Make sure headlights, blinkers and radios are off in both cars.
- Make sure both cars have the parking break on and are either in park or neutral.
Most car batteries are located under the hood of the car. Some smaller or older cars have the battery stored under the back seat or in the trunk. Every car battery has a positive (+) terminal indicated by red or orange wires, connections or cover, and a negative (-) terminal indicated by black wires, connections or cover. You may have to remove a battery cover or plastic cover in order to reach the battery terminals. Before the jump start, if you see any dust or dirt around the battery terminals, use the wire brush to remove this debris.
The Jumper Cables:
To jump start a car, you need to make a circuit that will carry current from the live battery to the dead battery. As car batteries loose fluid or discharge, a buildup of hydrogen gas can occur in enclosed spaces. Loose jump start cables could cause dangerous sparking, and ignite this gas. To minimize risk, connect the jump start cables in the following order:
- Connect one end of the positive jumper cable (red) to the positive post (+ or red) of the dead car battery.
- Connect the other end of the positive jumper cable (red) to the positive (+ or red) post of the charged car battery.
- Connect one end of the negative jumper cable (black) to the negative (- or black) post of the charged car battery.
- Connect the other end of the negative jumper cable (black) to a solid, non-paint coated metal part of the engine of the dead car, As far from the dead battery as possible. This grounds the circuit.
To minimize risk of explosion, do not connect this last cable directly to the dead car battery itself. Before you jump start a car, make sure cables are not touching any moving engine parts.
Ways to Jump Start a Car:
- Start the engine of the car with the charged battery and let it idle for five minutes to charge the dead battery. Shut off the engine of the car with the charged battery. Disconnect all cables in reverse order being careful not to let the cables touch. Start the engine of the dead battery.
- Start the engine of the car with the charged battery and let it idle for five minutes to charge the dead battery. Try to start the dead car battery without shutting off the engine of the car with the charged car battery. If it won’t start completely, allow a few more minutes of charging and try again.
If you’re in ever in doubt, stop what you’re doing and contact AAA, your mechanic or a local service station for assistance with your jump start.