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The process of starting your battery is simple and efficient in one pinch, but it is important to do it properly to avoid sparks or injuries. We will show you how.
See us all Autoblog Ranched Video of more tips on how to diagnose, fix and repair a car from professional dealer Larry Kosila. While you’re at it, watch a video series of Larry’s other car cleaning and maintenance Autoblog Details!
Instructions (video transcript):
[00:00:00] – [Larry] When you have a weak or dead battery, it is quick and easy to start your car from another person’s electrical system. But keep in mind, it can be a challenge to do it safely in the order in which it is done without sparking or arching. For this, you will only need a jumper cable and a functional second car. I am Larry Kosilla, Pro Detailler and Trainer, for the last fifteen years. But when it comes to what happens under the hood, I’m a student. Follow me as experts teach me how to diagnose, repair and modify cars on Autoblog Wrenched. Okay Spence, it seems pretty easy to start your car with a jump. Red on red, black on black, start the car
[00:00:30] And this one should start. Which way does it work? – Okay, theoretically you are right, but there is a certain order where you want to put the wires. You don’t want to damage the car factory ECU and you certainly don’t want to create a spark or perhaps blow up the battery acid smoke on a dead battery. – [Larry] Quality jumper cables come in different lengths, colors and prices but the most important factor is its gauge. The lower the gauge, the more power can be transferred through the cable and so the battery will be charged
[00:01:00] Faster and more efficiently. Similarly, find a clamp with strong claws and closing strength, a rubber insulated cover, to reduce the chances of being pushed and at least twelve feet in length. Open the hood of a good car, which may not be your familiar car, and identify which side of the car the battery is on. Try to arrange the cars in such a way that you are not working between two cars if they accidentally roll or assign a gear. But the bumper should not be touched. Always make sure every car is in the park
[00:01:30] And all accessories, such as radios and blower fans, are turned off, e-brakes are fitted, and pull the car keys to prevent your assistant from accidentally starting it while you’re under the hood. Now leave both cars off, start with the dead battery. But first untangle your wires and make sure the four leads are not touching each other before connecting to the battery. A common mistake is when one side of the wire rests on top of the other, unknowingly, when connecting to the other side. If this happens, a pressure or a spark can occur,
[00:02:00] Which is harmful to the battery and can ignite. The first step is to attach the first red, or positive, cable to the dead battery. This is because this particular battery has minimal power so it makes you less likely to have a problem. The battery will have positive and negative signs and usually has a black for red, positive and negative. Make sure your black lead is resting on plastic and not metal, if possible. For the second step, repeat the same process on a good battery
[00:02:30] And reconnect the positive side. So, now both batteries are connected by their positive wires. For the third step, connect a negative or black wire to a good car battery terminal. For final connection, do not connect to battery. Instead, look for a shiny metal that can be attached to the engine block or alternator, but avoid any metal that can carry fuel or be close to the belt or fan that rotates when the car is turned on. As always, it may recommend your manual advice
[00:03:00] A suitable attachment point. With both wires properly connected, turn on the good car and let it run for five to ten minutes. The good car alternator is charging both its battery and the battery of the dead car. Now get in the dead car and try to turn it on. If it does not turn on immediately, let it sit on the charge for another five minutes. If a second attempt is required, get your helper in a good car and bring the engine back to two to three thousand RPM to increase the output.
[00:03:30] To run it in the hope of giving the dead battery a little extra juice in the hope of an alternator. Similarly, double check if your connections are strong with the battery or try another ground location, if all else fails. Once the dead battery starts, disconnect the cables in reverse order from the way they were installed. Wrap the wires and place them in your trunk and check your battery immediately at your dealer or auto parts store. If the battery loses its charge, it may be time to replace it. Bypassing a dead battery with jumper wire
[00:04:00] You can get yourself back on track and run, but it’s not usually a fix. This is more of a bandage until you or a mechanic find the root cause of the battery drain. For more videos on car repair, visit autoblog.com/wrenched. I am Larry Kosilla from Ammonyc.com. As always, thanks for visiting.