Connecting or disconnecting a car battery appears simple. However, it’s among the most confusing exercises to go about, regardless of how easy it is to just pull off or put back battery cables from/to the battery terminals.
One major contemplation is whether or not to attach negative or positive first when going about attaching the battery cables to the terminals. That same contemplation applies to the process of disconnecting.
This is therefore a guide to provide a simple solution to your contemplations. You will learn why it is important to connect battery cables properly, and also the dangers of going about it the wrong way. Let’s push aside our contemplations below.
Which car battery terminal to connect, positive or negative first?
Knowing which terminal to connect first – positive or negative – when connecting a battery can be quite tricky without a little helpful guide.
Here it is – connect the positive terminal first when connecting a battery before the negative terminal.
The BIG QUESTION is – why connect the positive terminal first? The answer is simple and straightforward – it is the safety inherent in the whole connection process.
Connecting the negative terminal first before the positive terminal can ignite a big spark or arc through you when the spanner, or wrench you’re using to tighten the positive cable, touches any metal part of the car.
Basically, to prevent a deadly electrocution or fire, ensure that you attach the positive cable to the positive terminal first before fixing the negative cable in place on the battery’s negative terminal.
Which car battery terminal to remove, positive or negative first?
Again, knowing the order of positive and negative first when removing the battery can be a bit puzzling. The cables aren’t just plain wiring you can randomly remove on disconnecting the battery.
So, take care to first remove the negative battery terminal, before the positive terminal. If you remove the positive terminal first, before the negative, the wrench you use in removing the positive cable may touch the car’s body (the metal surface), or the engine block, and generate a serious spark that could destroy the battery.
Simply follow the reverse order of connecting the car battery, therefore. While the connection procedure begins with the positive terminal, the disconnection procedure begins with the negative terminal. For more guides, check out how to safely disconnect the car battery.
FAQs.
Q: Why do you put the positive terminal first?
When connecting the battery cables of a car ensure you put on the positive first before the negative cable.
This is because the positive cable will not arc, if while tightening up the cable your wrench or spanner touches the car’s body, because there is not ground (negative cable).
In other words, attaching the negative cable first will pose a possible dangerous outcome in the process of attaching the positive cable and tightening up the same.
This is because once you have already connected the negative cable before the positive cable, when the wrench touches a metal part of the car accidentally in the process of connecting the positive cable, it will arc through you or lead to a fire outbreak.
Q: Do you hook up red or black first?
Well, even if you have not paid attention and are now wondering if the correct operation is red or black first when jumping a battery, remember to fasten the red cable first when jump-starting a car.
Carefully clamp one side of the red cable on the positive terminal of the dead battery and fasten the other part of it on the positive terminal of the lively battery.
If you fasten the red cable first, that helps prevent damage if the other part accidentally touches that frame or any metal part of the other vehicle.
Then clamp one side of the black cable on the lively battery and fasten the other part to any metal part of the car, frame or engine block.
When you are sure of good connections, start the lively battery car and then run the engine for a while.
Then, slip into the car with the flat battery and turn on the ignition and start the engine. There goes the confusion of red or black first when connecting batteries to jump-start a car.
Q: Do you put the negative on first?
No! You will be playing with fire if you connect the cable to your car’s battery negative terminal before the positive cable. In other words, it is positive first before negative to prevent electrocution or fire outbreak.
Knowing how to tell positive and negative on a car battery is necessary at this point; they are marked (+) for positive and (–) for negative respectively.
Now, should you mistakenly attach the negative cable first, a slight error whereby the wrench used in tightening up the positive cable touches the car gets you shocked and probably sparks up fire right away.
It then pays to follow the work of connecting a car’s battery as recommended without any compromise. Connecting a car’s battery in the recommended method can be quite easy if you are a DIYer. Otherwise, kindly call in an expert auto technician.
Q: Why is the negative terminal disconnected first?
The negative (grounded) terminal is disconnected first in order to avoid a battery dead-short occurrence.
Otherwise, it can result in a shock or spark up a fire in case the wrench used in disconnecting the positive cable touches the car’s frame or grounded metal surface.
That means disconnecting the positive cable first puts you and the car at risk. This is because there is a tendency for the wrench used in removing the cable to contact a grounded metal surface on the vehicle, resulting in a shock or fire.
So, kindly stick to the proper order while connecting the battery terminals.
Q: Which jumper cable comes off first?
The black (negative) jumper cable is first to be removed after jump-starting a car. It is simply the reverse order of connecting the cables at first.
So, once your car starts after jumping the dead battery, carefully detach the black cable’s clamp on the metal surface (frame or engine block), followed by the other black cable’s clamp on the negative terminal of the dead battery.
After that, detach the red cable’s clamp on the lively battery or the jump starter and remove the other end from the dead battery’s positive terminal. Then, you are good to go!
Q: Does positive go first when jumping a car?
If you’re asking, is it positive or negative first when jumping and you are confused, know that the positive cable goes on to connect to the positive terminal of the flat battery and the lively battery first before the negative cable.
It is the same if you are confused is it positive or negative first when charging a battery.
The positive jumper cable is normally red, while the negative cable is black. The positive (red) cable is usually connected first and removed last.
So, if your car fails to start due to a flat battery, ensure to jump-start the car with your neighbour’s jumper cables.
But be careful to connect the positive cable first, followed by the negative cables. When you are done jumping the battery, remove the negative cable first, and then the positive cable.
Q: Does it matter what order you connect the jumper cables?
It is imperative to know if it is positive or negative first when jumping a car because the order of connecting and disconnecting jumper cables is crucial when it comes to jumping a flat battery.
The procedure is not a mere traditional process with no implications. It could spark up fire and also damage your car if done upside down.
Please do not make the mistake of connecting the other end of the black cable (negative) to the dead battery after connecting the first clamp to the lively battery’s negative terminal. It could be quite an expensive damage.
Q: Do you turn off your car before removing jumper cables?
Do NOT switch off your car before removing the jumper cables once your engine is up and running. You could experience starting your engine without the jumper cables connection especially when the dead battery is not yet fully charged.
You should always remove the jumper cables while your car is still running. Ensure that no clamp is in contact with the other while removing the jumper cables. Also, remember to: remove the negative cable before the positive one.
By the way, if you are asking, “Is red positive or negative”, of course, red is the positive, while black is the negative.
Q: Is it OK to just disconnect the positive terminal?
No matter what, it is good practice to disconnect a battery’s negative terminal rather than the positive one. Though you are trying to prevent the battery from discharging, you may likely achieve that when you disconnect positive or negative first.
In fact, it is okay to disconnect just that one cable. Just one cable will produce an open circuit that cannot enable a current flow.
On the other hand, disconnecting the positive terminal while the other negative terminal is still connected may prove fatal by electrocution or sparking a fire. So, do not.
Final Words
There’s no need to compromise safety in handling mechanical or electrical parts that could be dangerous. To carry this out could injure you badly or destroy the part, plus the accompanying items embossed with target ranges.
When connecting or disconnecting the car’s battery, don’t even think which is positive or negative first; simply turn to your owner’s manual and follow the procedure laid down there. If you don’t have one, consult someone. Like that information you’ve just read in this article, for example.
If there’s someone who you think will make a DIYer in no time, turn him or her on to this article and he/she will learn the ins and outs of basically connecting and disconnecting the battery.