There can be many reasons for a car battery to run out of power, including not starting the car for a long time, parking the car in a cold environment, not turning off the headlights or interior lights after parking, etc. To charge a flat battery, you’ll need a set of jumper cables and a charged car. Then you need to use jumper cables to connect the batteries of the two vehicles so that the electrical energy in the charged battery can be transferred to the dead battery. Continue reading this article to learn the detailed steps for safely and effectively using jumper cables for your car battery.
Preparations before Starting the Car
Check the appearance of the car battery before starting. The battery should be in good condition, with no cracks and no obvious signs of battery acid leakage.
- If the car has any of the above damages, do not start the car to avoid injury to yourself or others.
Wear safety goggles and rubber gloves before handling your car battery. Goggles and gloves will protect your eyes and hands from the concentrated acid spilled from the battery.
Make sure jumper cables connected to the car are safe and corrosion-proof.
- If the battery cable is corroded, use a stiff brush to clean it if possible.
Park your car with a full charge next to the car that needs charging, but make sure the two cars are not touching. The ideal situation is to park two cars next to each other in the same direction or park the fronts of the two cars opposite each other.
- Make sure that the jumper cable can connect the batteries of both vehicles. The length of jumper cables varies greatly between different models and manufacturers.
- Don’t try to connect two different pairs of jumper cables together if the first pair is not long enough. Failure to do so may cause the jumper cables to melt and cause a fire.
Turn off the fully charged car.
Starting a Car That Has Run out of Battery
Open the hoods of both vehicles and find the battery.
Remember the positive and negative terminals of each battery. The positive terminal is marked with a plus sign (+), while the negative terminal is marked with a minus sign (-).
Connect both ends of the positive jumper cable to the positive terminals of the batteries on both vehicles. Positive jumper cables are usually red unless otherwise marked. Connect one end of the positive jumper cable to the dead battery and the other end to the fully charged battery.
Connect one end of the negative jumper cable to the fully charged battery. In most cases, the negative jumper cable is black.
Connect the other end of the negative jumper cable to a grounded metal part of the car. This will allow a car that has run out of battery to start. You can connect the ground cable to the frame, chassis, or other parts that are clean enough and free of paint and oxidation.
Start the vehicle engine with a normal battery. While starting the engine, the vehicle’s charging system will begin charging the dead battery via the jumper cable.
Charge for at least 5 minutes after starting the engine. This will cause the dead battery to start charging itself, although doing so will take longer to fully charge the battery.
Try starting a dead car engine. If the jumper cable and the charging battery have enough power, the car engine can start easily.
- If it fails to start successfully, please charge the battery for another 5 minutes.
Remove jumper cables in the reverse order of connections to avoid sparks or explosions. If you connect the negative jumper cable to the negative terminal of the dead battery first, remove it last.
- Disconnect the ground wire first, then the cable connected to the negative battery terminal, then the jumper cable connected to the positive battery terminal, and finally the cable connected to the positive terminal of the previously dead battery.
A depleted car should be started for at least 5 minutes to allow the alternator to charge the battery.
After starting the car, drive or idle for at least 20 minutes. Sometimes the battery can be fully charged within this time; if the battery is not charged enough to drive the car, it may be necessary to replace the battery with a new one.
Tips
- An auto parts store can quickly test whether the battery is ready for further use.
- Check the electrolyte level in dead batteries to ensure adequate charging.
- The larger the diameter of the jumper cable, the faster it will charge.
- If idling is extended for some time, you need to pay attention to the temperature of the vehicle, as some cars may overheat during extended idling.