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How to jump start a car

When your car battery fails you, jump-starting it often solves the problem. While it might be a fairly straightforward process, jumping the can be dangerous if you do not take the necessary precautions.

The best advice, however, is that if you do not have experience jump-starting a car or are unsure about your skills, it is best to let a professional do it to avoid damaging either or both vehicles.

Nevertheless, we will let you in on all you need to know about how to jump start a car as it might be a situation where you will have do to it yourself.


Here are the tools you require:

  • A pair of jumper cables with rust-free clamps
  • Rubber work-gloves
  • A pair of auto repair-rated splash-proof safety goggles
  • Wire brush
  • Another vehicle with a battery that has the same voltage as yours and is fully charged.



car battery being hooked up by cable jumpers: how to jump start a car


What You Should Do When Jumping the Vehicle?

Well, to be frank. Read Your Owner’s Manual

Before you attempt a jump-start, first read this manual as it may contain information that affects the process you are about to embark on. For instance, new car models are coming with jump-start lugs where you can attach the cable rather than attaching to the terminals directly.

Moreover, some manufacturers do not allow their vehicles to be jump started. Doing so could see you void your warranty. Other vehicles come with special instructions on how to properly carry out this process.


  • Check the Battery Voltage on both vehicles
  • Bring the Vehicles Close to One Another
  • Ensure the engine of the car with the fully charged battery is off
  • Device chargers and other accessories should be unplugged.
  • Have both cars in neutral and be sure to engage the parking brake.
  • Radios, headlights, and other signals need to be off in both cars.
  • Put on your safety goggles and rubber gloves.

What You Should NOT Do

  • Do not lean over either battery.
  • Do not smoke.
  • Do not jump-start a car that has frozen battery fluid as it could lead to an explosion.
  • Similarly, do not jump-start a cracked or leaking battery as it may explode.


After following the above steps and precautions, the next step is to locate both cars’ batteries. As mentioned earlier, vehicles today are configured differently, and as such, the battery might not be in an accessible location. In such a case, look for the lugs.

After locating the battery or lugs, examine them carefully to be sure where the positive and negative terminals are in each vehicle. The positive terminal is denoted by the (+) sign and usually has red wires and a red cover while the negative (-) terminals typically have black wires and cover. You might have to move the terminal covers to get to the actual terminal. If your battery has a case of dirty or corroded terminals, clean them using the wire brush.


How to jump start a car: The Procedure

To carry out a proper jump-start, you’ll have to create a circuit in order to carry over current from the good battery to the dead one. This is the exact order you will follow when connecting the cables:

  1. Connect the positive (red) terminals of both cars using the red cable. When connecting, first attach the cable on the good car’s battery first then the dead battery.
  2. Now connect one end of the negative (black) cable to the negative terminal of the car with the good battery.
  3. Place the unattached end of the black cable to a metal part of the car with the dead battery. That metal part needs to be unpainted and as far away from the battery as it can. The purpose of doing this is to ground the circuit so as to prevent sparking. When you connect that end to the dead battery’s terminal, you be running a risk of the battery exploding.
  4. Now make sure that none of your jumper cables are touching an engine part that will start moving once the engine is started.

When it comes to jump-starting a dead car’s battery, there are technically two ways you can go about it:

• The Safe Way

Here, after connecting the cables as explained in the section above, start the engine of the car with the good battery and let it idle for a few minutes (five to 10 minutes) so that it charges the dead car’s battery. Once those 10 minutes are over, turn off the car and remove the cables starting with the dead car. While removing the cables, be careful that they do not touch each other as it might result in sparking. Now try and start the engine of the vehicle that had a dead battery.

• The Other Way

Again, start the engine of the car with the fully charged battery and let it idle for the prescribed ten minutes to let it charge the drained battery. Without switching off the engine or removing the cables, try and start the car that had a dead battery. If it doesn’t come to come to life, let the good car continue running for another ten minutes.

If the vehicle with the dead battery still won’t start, readjust the positioning of the red (positive) cable to a small degree with the hope of getting a good connection. Try and start the dead car’s engine again. If it, hopefully, comes to life, remove the cables starting with the previously dead car while being cautious not to let them touch.

If it doesn’t start despite all your efforts, it could be indicative of a larger issue. At this point, you should call a trusted mechanic.



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