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.
Why should you disconnect the negative battery terminal 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 .
What happens if you disconnect the positive terminal first?
It's important to disconnect the negative side of the battery first , otherwise you can cause an electrical short if the positive is removed first.
When installing a car battery which terminal do you connect first?
“ Positive first, then negative . 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.”
What happens if you don't disconnect the negative battery cable?
The electrical power in a car's engine is activated by the battery. Contact between the negative battery terminal and the battery, even if the cable is not clamped onto the battery, may reactivate the electrical system within the car .
Is it OK to just disconnect the positive terminal?
You will be fine. Disconnecting either cable works . The reason they say to disconnect the negative and not the positive is because while taking the positive connection off with a wrench if you happen to touch anything with the wrench while it's on the positive terminal it can arc and be dangerous.
Whats positive red or black?
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.
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.
What happens when you connect the positive and negative ends of a battery?
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.
What happens if you connect a car battery wrong?
When the jumper cables are incorrectly connected, the polarity of the electrical system on the vehicle with the dead battery will be reversed for a few seconds . This can irreparably damage many of the sensitive electronic components that are common on today's vehicles, such as on-board computers and electronic sensors.
Can I touch battery terminals?
In fact, under normal conditions, a 12-volt car battery will usually not even shock you. ... That's why you can touch both terminals of a car battery without receiving a shock , although you may feel a tingle if your hands are wet.
Do I have to disconnect both battery terminals?
The grounded terminal should be disconnected first to ensure that a battery dead-short does not occur, should the spanner disconnecting the other one contact a nearby grounded metal part. A battery dead-short will result in short circuit currents of the order of hundreds of amperes and heavy sparks.
Which battery terminal Do I disconnect for storage?
If you plan on storing a vehicle for an extended period, it's advisable to disconnect at least the negative terminal from your car battery. This prevents unnecessary battery drain, as a fully charged battery can hold its charge for 6-12 months if you do this.
Should I disconnect both battery terminals?
Disconnect the Battery Cables
The terminals will be marked positive and negative. Make sure you disconnect the negative terminal first . ... While loosening the cables, be sure not to touch your wrench to both terminals at the same time, because this will allow electricity from the battery to flow through your wrench.
Which cable do you disconnect to check alternator?
If you're tempted to test an alternator by disconnecting the negative battery cable , don't do it. A good alternator may indeed keep the engine running without the negative cable, but this was never a good test. In the pre-computer days, you could pull it off without damaging anything.
Should I disconnect battery if car parked long term?
“If someone is going away for a few months over the winter, they should definitely disconnect the battery. It's the only way to prevent battery drain ,” Rashidi said. ... I would recommend taking the negative battery post out, and wrapping something around the end so it doesn't touch anything while you're not there.”
