How to Check and Replace Your Car Battery Cables

You planned that exciting trip to the mountains with your family for a long time. Now it has turned into a nightmare and you are stranded in the middle of nowhere, all because of a faulty battery cable connection. It is not uncommon, yet it is something easy to avoid. The starting and electrical systems in your vehicle need a good connection to the battery to draw the required electrical current to function properly. Fortunately, proper maintenance of the battery cables is a simple task. Here we will learn how to check the connection between the battery and battery cables, and how to replace them if necessary. No need to be stranded in a remote and possible unsafe place anymore.

Things You'll Need

  • Combination wrench set
  • Wire brush
  • 8 oz. foam cup with a solution of baking soda and water
  • Rag
  • Petroleum jelly
  • Inspect the length of both battery cables looking for cracked, burned insulation and corrosion that might be wearing away the cables. Corrosion usually shows as light and soft white powder on the battery terminals.

  • Clean the corrosion by disconnecting the cable from the battery terminal, starting on the negative side of the battery. Use the correct wrench size for the terminal bolt. Use a wire brush to clean the corrosion off the battery post and cable terminal until you see no traces of the white compound.

  • Use a solution of 1 tbsp. baking soda and 8 oz. of water mixed in a foam cup to dip the battery terminal into and clean the corrosion from hard to reach places. You can also pour some of the solution onto the battery post and wipe it clean with a rag. This will help the corrosion from building up so quickly.

  • Check the smaller wire going from the negative battery terminal to the body of the vehicle. Make sure it is not corroded or loosed.

  • Replace both battery cables if the insulation is damaged or corrosion is far advanced into the wire in either one of them.

  • While working at the negative side of the battery first, disconnect the terminal from the battery post. Trace the other end of the cable to disconnect it from ground.

  • Disconnect the positive terminal from the battery post and the opposite end at the starter solenoid.

  • Replace the battery cables with ones of the same size, gage and battery terminal.

  • Bolt the respective cables to the starter solenoid and ground-making sure the connections are clean-and secure the terminals to the battery posts.

  • Apply a layer of petroleum jelly to the battery posts and terminals to prevent corrosion from building up.