How to put the clamps to start the car

Have you run out of battery and the car won’t start? If you have cables with clips, you can fix it yourself.

Your car’s battery can discharge because you have left something on (the lights, the radio or a door not closed properly) or simply because your car has been stationary for several months and the battery has discharged itself. You can take it to the workshop, but it is easy to save labor and even changing a new battery that you may not need (if it discharges again soon you may, read our five tips for buying a new battery first). As you will see below, it is very easy to start a car with pliers.

First step

The first thing is to have some clamps on hand for the car, which will be used to transfer energy from a full battery to the empty one that the other car has. The longer the starter cables (normally one red and the other black) the easier it will be to place them and the less maneuvers will have to be done to place the cars. Furthermore, it is essential to always maintain bodywork separated of both cars to prevent a short circuit or spark from occurring.

The tweezers The cables that are part of these cables can be of different shapes, but they must all have enough pressure to be able to firmly grip and hold the battery terminals. He red cablewith clips of the same color, is used to interconnect the positive (+) terminals, while the black wirewith the black clamps, are used to interconnect the negative (–) or “ground” terminals of the batteries.

By securitybefore bridging the batteries of two cars, completely turn off the start switch in both cars and set the handbrake on each. You should also prevent any fan or auxiliary electric motor from starting before starting the car’s main engine with a discharged battery.

Second step

Once you have the tweezers, you have to locate where the batteries are in the cars. Normally it is under the hood of the car, but not always, since in some cars it is located under the rear passenger seat, for example.

Once the two batteries are located, identify their positive and negative terminals (the positive has the plus sign +). Start the connection: Place one of the clamps on the red wire on the positive terminal of the battery loaded car.

Third step:

Place the clip on the other end of the red wire into the positive (+) terminal of the discharged car battery. Check that the cable is firmly attached to both sides and that it cannot come loose from the terminals inadvertently: this will prevent a short circuit from occurring if they touch any metal part of the car or the other terminal of the battery.

Fourth step:

Once the two clamps of the red cable are fixed, it is time to place one of the clamps of the black wire (minus sign ‘-‘) on the negative terminal of the battery that is charged.

Fifth step:

There is only one side of the black wire. It does not go to the negative terminal of the unloaded car. You have to set it in some metal part of the frame, of the chassis, or of the engine block of the car that has a discharged battery (without paint so that it makes good electrical contact). Why not to the negative terminal of the discharged battery? For safety reasons: This will prevent an explosion from occurring if there is a hydrogen gas leak when connecting said clamp directly to the battery terminal. But if you cannot find any appropriate point on the chassis to connect the clamp, there will be no other alternative than to do so directly to the negative terminal of the discharged battery. Of course, make sure first that it does not have any type of deterioration.

In any case, to prevent this type of problem, always fix it away from the battery and other places where there may be fuel. By avoiding putting it on the negative terminal, a common “ground”, “negative” connection is created for all the equipment and devices installed in the car. In this way, manufacturers manage to save a good number of cables in the entire electrical installation of their cars.

Check that the cables with which you have connected both batteries do not rub against any mechanism that starts moving when the engine starts (fan, belts…). This will prevent any clamps from coming loose or damaging the cable lining and causing a short circuit.

Sixth step

Once the last checks have been carried out, start the engine of the car with the charged battery, accelerate a little and keep it running for a few minutes so that the battery is properly recharged. This will prevent this battery from having to overexert itself when trying to start the other car’s engine.

After a few minutes, turn off the engine of that car and immediately try to start the engine of the car with a dead battery. When it starts, give it a little throttle and keep it running for a few minutes to give the battery a little charge. After starting the car with another battery and traveling a few kilometers, it should recover the charge and present no more problems to start the engine again.

Once the engine starts well, Remove the clips from the car in the reverse order of how they were placed.. Be careful that they don’t touch each other or any metal parts of the car!

What if it doesn’t start?

If after making several attempts the starter motor does not have the power to start the car (or does not even make an attempt), check to see if any of the clamps have become loose or are not making good electrical contact. Try again, but if the problem persists you will most likely need to replace the battery with another one. It may also be another element of the car’s electric starter… but then there will be no choice but to visit a mechanic to check the electric starter circuit and the spark plug circuit.

What if it downloads again immediately?

It is likely that the glasses are missing distilled water, or that the battery is already worn out or “sulfated”, having reached the end of its useful life. If after filling the glasses with distilled water and traveling a few more kilometers the battery still does not hold a charge, then it is best to replace it with a new one or try to give it a full charge using a battery charger.

Also if we have a backup battery stored in the garage and we always keep it fully charged, we can replace it in the car with the one that is discharged, or also connect it by means of a jumper to the battery of the car that has it discharged, using the connecting cable set referred to and following the steps explained above. This way it may not be necessary to use that of a second car.

More information: This is how it works

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