What happens if you connect the negative terminal first?

Connect positive first, negative having less potential won't arc. The higher the voltage, the greater the chance of arcing and fusion. On a car if negative first and you are touching any metal part of car, when attaching positive there is possibility of arcing through you. Your body becomes part of the circuit.
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Should I connect the positive or negative first?

When disconnecting the cables from the old battery, disconnect the negative first, then the positive. Connect the new battery in the reverse order, positive then negative.” When you are replacing your car battery, It isn't always easy to remember the order in which to disconnect and reconnect the terminals.
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Why shouldn't you connect the negative terminal?

Tip #1: Never connect the black cable to the negative (–) terminal on your dead battery. This is very dangerous, as it could result in an explosion.
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Why is negative terminal disconnected first?

By removing the negative battery cable you are disconnecting the battery from the chassis of your vehicle. If you begin to remove the positive side before the negative and your wrench would make contact with any part of the vehicle, then you could cause a short in the system.
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What happens if you connect negative to positive?

Connecting the battery terminals in reverse can cause serious damage to the battery itself, the electrical components, and even to yourself. Each terminal of a car battery uses 12V of current with positive and negative orientation.
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Which battery terminal to disconnect first, connect first?



What happens if you connect jumper cables in the wrong order?

Fuses (and/or fusible links) act as circuit protection devices between the battery and the vehicle's electrical system. Connecting the jumper cables backwards will often result in one or more blown fuses. The affected circuit will not function correctly until the blown fuse is replaced.
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Does it matter what order you connect jumper cables?

Don't attach the negative (black) clamp to the negative terminal of the dead battery. It is important to connect the cables in that order, and it is safest to connect the negative (black) clamp as far from the battery as possible, in order to reduce the risk of sparking that could cause a fire or explosion.
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Does it matter which battery terminal I disconnect first?

Disconnect the Battery Cables

Make sure you disconnect the negative terminal first. Lay the disconnected negative cable carefully to one side, making sure it's well away from the battery terminal. Disconnect the cable from the positive battery terminal in the same way, then lay it to one side.
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Is it OK to just disconnect the negative terminal?

Disconnect battery negative cable

It is a good practice to always disconnect your negative battery terminal first, to minimize the risk of sparks that can lead to car electronics damage and battery explosion. Once you have located the negative terminal, use the wrench to free the nut that tightens the terminal.
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Can jump-starting hurt car?

Like most electronics, a power surge can cause damage to the electronic systems of a modern car. A seemingly well-meaning jumpstart can cause said power surge and impact the effectiveness of onboard computers, safety systems, damage the engine and be the result of expensive repairs.
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Can you use the negative battery terminal as a ground?

Active member. Re: Is battery negative and \'ground\' the same thing? The short answer is yes, you can just connect the ground to 0 Volts.
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Can you get shocked by a car battery?

Car batteries can provide high currents. And yet they won't electrocute you. The key to this curiosity is that it is current running through your body that does the damage, and not the maximum current that a battery can provide.
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What happens if you connect battery terminals together?

If you connect a wire between the two terminals, the electrons will flow from the negative end to the positive end as fast as they can. This will quickly wear out the battery and can also be dangerous, particularly on larger batteries.
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Why do you connect positive terminal first?

Connect positive first, negative having less potential won't arc. The higher the voltage, the greater the chance of arcing and fusion. On a car if negative first and you are touching any metal part of car, when attaching positive there is possibility of arcing through you. Your body becomes part of the circuit.
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Which wire do you connect first?

The negative () cable is the ground cable; it is always connected to the frame or body metal and can safely be disconnected first with no chance of causing sparks. By the same token, always reconnect the positive cable before connecting the negative cable.
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Do I disconnect the positive or negative to check the alternator?

You can check the alternator by simply starting your car and then disconnecting the negative battery cable. Be careful doing this, though, because there are a lot of moving parts in your engine compartment that could cause injury.
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Is black negative and red positive?

The red one is positive (+), the black one is negative (-). Never connect the red cable to the negative battery terminal or a vehicle with a dead battery.
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Should a battery disconnect be on positive or negative?

The negative cable connects to the body ground already—so there's no additional danger if it rubs. It's the same principle as why you should always disconnect the battery's negative side first before performing electrical service.
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When jump starting a car always remember positive to negative?

Turn off the ignition on both cars. First, clamp one end of the positive cable to the dead battery's positive clamp. Now have a helper connect the other end of that cable to the other battery's positive clamp. Next, connect the negative cable to the negative terminal on the good battery.
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When placing the black jumper cable on the dead car put the clamp on?

Connect one black-end clamp to the negative (-) post of the good battery. Carefully connect the other black-end clamp to some large metallic part of your car's engine block. Never connect it to the negative (-) post of the "dead" battery. This causes sparking, which could ignite battery gases.
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Do you turn off car before disconnecting jumper cables?

This can result in a very dangerous electrical arcing situation that can cause damage to people and vehicles. Don't let your jumper cables hang loose around the engine. They can potentially interfere with moving parts. Make sure both cars are off with the keys removed before connecting the cables.
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What happens if battery polarity is reversed?

The heat produced by the reverse polarity in the battery may cause hydrogen gas (ignitable) which may explode the battery casing. The cracked case of the battery may provide a way for acid which may melt the sensitive devices and cause serious injuries as well.
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Can jumping a car wrong ruin your alternator?

Jump start your car correctly

These boxes enable the jumpstart to occur with no risk of damage to the starter or alternator. The next option is to “jump” the vehicle with a vehicle that has a “good” battery. When doing this, make sure the vehicle that is providing the jump is “off” and the key is out of the ignition.
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