Which battery cable should be taken out first and which one installed last?

Whether you need to jump start the car or it’s time to replace a battery, you must know the proper way to disconnect and reconnect the cables. You should know which battery cable to remove and then install last. If you don’t get the answer right, you could put yourself in danger.

Always remove the negative cable first, and then replace it last. The positive cable should always be removed first and then replaced last. For everyone to be safe, it is important that you take the proper precautions with your battery. 

We will be discussing the main reasons why the negative cable should not be removed first. This guide will also assist you in identifying the battery cables, and explain why it is so important. 

How to identify battery cables

You should color-code or mark the battery terminals of your car. The terminals should be marked with a positive symbol for the positive terminal and an minus sign for the negative.

There’s also the chance that the caps are color-coded. The red cap indicates the positive terminal and the black one the location of the negative terminal. Your car may include symbols or colors if you're really fortunate. This will make it easy to identify. 

What Battery Cable should be removed first?

Always remove the negative cable of your battery from its connector. You will find the terminal's negative end with either a plus sign or black cap. This is a simple way to avoid electric shock or spark.

You will need a socket wrench to disengage the battery cable. This is usually 10mm. You will need to place it on the connector bolt. The socket should become looser if the wrench is turned counterclockwise. You should make sure that the socket does not touch both terminals simultaneously, otherwise you could create an electric pathway.

You should remove the negative cable and put it away. Don’t let it touch the battery or positive terminal. 

Related: 6 Signs that a Negative Battery Cable (Bad Ground Strap)

What Battery Cable should be reconnected last?

You should install the positive battery cable first, then the negative one. It is important to properly connect the cable after installing a battery or jump starting it. Follow the same steps as you did to take out the terminals. 

These guidelines will help you connect the positive terminal. You can then connect the negative terminal. 

RELATED: Battery Terminal Corrosion Causes (How to Fix & Prevent It)

Do Negatives Need to Be Disconnected First?

Failure to disconnect the battery's negative terminal first can lead to an electric short. For example, an electric short could be created if a metallic tool is dropped on to the positive terminal. 

Your battery will be affected by this problem. You could also be subject to severe shock. That’s why the negative cable should always be the first off and last back on. 

However, it’s also just as important that the connectors don’t touch each other or anything else while you have them disconnected. You can attach the connectors temporarily using a zip tie, or other item. Just make sure you don’t let them touch anything made from metal. 

After you have reinstalled the connectors, remove the zip ties. Make sure to always attach the positive cable first. To ensure the perfect connection, give both connectors a firm wiggle. 

Don’t be alarmed if you see a small spark when you put the negative cable back on. It is a sign that the circuit has been reestablished.