How to Remove a Negative Battery Cable

Removing the negative battery cable first protects the battery from damage.

Before cleaning or replacing your car battery, you must remove the cables to ensure your safety. You should disconnect and remove the negative battery cable first. This prevents the battery from short circuiting if you accidentally touch another part of the car while removing the positive cable. Disconnecting the negative cable first prevents the car from completing an electrical circuit, making it more safe.

Things You'll Need

• Wrench

Instructions

1. Turn your vehicle's ignition switch off. Set the parking brake before attempting to remove your battery cable to ensure the car does not roll.

2. Look at the battery terminals located on either the side or the top of the battery. Determine the size of the bolt holding the battery cables in place. For instance, a 5/16-inch wrench holds the cables on several models.

3. Find the negative (-) sign located on the battery indicating the negative cable. The positive cable has a plus (+) sign. Some vehicles have a black cable for the negative and a red for the positive.

4. Loosen the bolt holding the cable onto the post by turning it counterclockwise, or to the left, with the wrench. Avoid touching the wrench to the positive battery terminal. Pull the negative battery cable off the post.

Tips & Warnings

• If the negative cable is difficult to remove, use a terminal puller to help remove it and prevent damage. Also, scrubbing it with a paste made from baking soda and water helps remove the corrosion making it easier to remove.

• Exercise caution when working with batteries and cables; since batteries contain a sulfuric acid electrolyte solution that produces a flammable gas and is very corrosive according to AmeriCredit.

References

• Handy Manly Ness: Removing and Installing a Car Battery to Replace or Clean It
• AmeriCredit: Learn 2 Replace a Car Battery
• Die Hard: Install Your Battery