How to Use Jumper Cables

What could be worse than walking out to your vehicle after a hard day only to find that the battery is dead? Perhaps you forgot to turn off an interior light or your battery has just reached its end of life. In either case, car batteries often do not indicate problems until it is too late, at which point your vehicle will not start.

No matter how old (or new) your vehicle is, you must have a working set of jumper wires and know how to utilize them. First, the proper pair of cables is required. When you truly need them, any set is better than none, but Popular Mechanics recommends purchasing cables that are 4 to 6 gauge and at least 20 feet (6 meters) in length.

Those extra-long wires will come in handy and make it easier to connect batteries if two vehicles cannot be parked immediately next to one another. Also search for extension cords with thicker wires and sturdy clamps. They will be more durable and long-lasting.

Obviously, when the moment comes to jump-start your battery, it is crucial to manage the connections correctly. Keep the red and black clamps from touching at all times, and keep the cables apart when you’re setting up, especially after you’ve connected the clamps to a live battery. If the clamps touch when they are “hot,” it could cause a short in one or both vehicles and will certainly result in sparks.

Since improperly using jumper wires might be hazardous, adhere to each step precisely. Most jumper cables come with an instruction card or label so that you can connect them correctly.

How to Connect Jumper Cables

  • Start by parking the vehicle with the healthy battery alongside the vehicle with the dead battery.
  • Locate the batteries of both vehicles by opening their hoods. If the battery posts are concealed by plastic hoods, remove the hoods to reveal the battery posts.
  • Locate the favorable (+) and unfavorable (-) posts. Positive posts may be red, but this is not always the case; therefore, it is advisable to search for a plus or minus sign to ascertain the polarity of a post. (Before attaching the clamps, make careful to clean the posts thoroughly.)
  • Then, obtain your jumper wires and connect one of the red clamps to the positive (+) terminal of the dead battery. Ensure that the clamp is securely attached. Attach the corresponding end of the same cable to the positive (+) terminal on the functioning battery.
  • Connect one of the black clamps to the battery’s negative (-) terminal. Ensure that the clamp is securely attached. Instead of connecting the other end of the wire to the dead battery’s negative terminal, clamp it to a bare metal surface on the engine of the dead vehicle, such as a bolt or screw. This will serve as the foundation for the jump start.

Jump Start the Battery

  • Start the engine of the working vehicle and allow it to idle for a few minutes.
  • Start the engine of the dead vehicle and allow it to idle for a few minutes.
  • If the dead vehicle starts without difficulty, remove the black clamp from the battery first. Then, detach the black clamp from the opposing vehicle.
  • Remove the red clamp from the healthy battery and then the dead battery.

It’s recommended to keep your vehicle running for an extended period of time to assist recharge the battery, but you should also consider getting its voltage tested to ensure it doesn’t need to be replaced.

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