How to Replace a Battery Cable for the Average Joe

To get to know your battery and cables, here are a few little facts:

Your positive cable is almost always red, and the negative or ground is always black in color. Your positive or red cable always goes fastened to your battery and then the starter solenoid, sometimes the starter relay. The negative goes to the ground and engine block, or side of the engine. A lot of manufacturers now use negative cables with no insulation, which can cause erosion in colder months. Most cars now have a body ground wire that has a loop that connects to your body with a screw, and this helps to ground the electrical system.

Now you should first start by taking off the negative cable from the battery. You can use pliers for this, or a wrench to get onto the nut or bolt, and unscrew in this manner. Get it completely off of the post on the battery, or you will be in for a shock later. Now there are different types of connectors. The one type I just told you about are the nut and bolts. The other type is a spring type cable, and to get it off you have to use vise grips. What you will need to do to get them off is to squeeze the prongs inward and at the same time lift it up and away from the battery terminal. Make sure you have a good hold on the cables while you are loosening them from the terminals. If you put too much pressure on the posts themselves, they will crack or break completely off. Unfortunately, if you do this, you will need a whole new battery because this one will leak until you get another.

There is a tool called a terminal clamp puller, and it can be used to pull the clamp up and off of the post. If you loosened the clamp correctly, you do not need this, as it will slip right up and off. Try not to use a screwdriver for this job, it will scratch up the cell covers and plates underneath the post. Now you want to track the cable from your hand to where it ends on the block and unbolt it from there. There is only 1 bolt, no matter what kind of vehicle, so you will not get lost finding it.

Now is the time to do the same with your red or positive cable. Simply loosen it and remove it from the terminal on the battery. Track this with your hand to the starter relay or solenoid, and unbolt it completely.

Now to get your new ones on, you want to reconnect the positive cable to the starter solenoid, and bolt it back on. Before you place the end back onto the battery, you want to clean the posts and connectors. You can use a wire brush to scrape the surface of each, and this will ensure a good connection. Put the red cable back onto the + side of your battery, and tighten the nut or bolt back so it holds your cable on the battery. Simply place the black wire back to the side of your engine block, and then reconnect to the battery terminal. Tighten it back down in the same manner you took it off, and start your engine.

You have just completed a home repair on your battery cables, and saved money and time by doing it yourself. Congratulations on your hard work.