Your car's battery is connected to the electrical system using a negative and a positive battery cable. The negative cable provides a ground for the battery, while the positive cable is "hot" and provides power to all of your vehicle's electrical components. The operation of your vehicle's charging system and all of its electrical components depends on a good positive battery cable. If your positive battery cable is heavily corroded or is more than a few years old, take a few minutes to replace it.
Open your car's hood. Disconnect the negative battery (indicated by a "minus" on the top of the battery case) cable from the battery terminal by backing off the clamp nut with an adjustable wrench in a counterclockwise direction. Lift the cable from the battery and push it aside.
Trace the positive battery cable from the battery (indicated by a "plus" on top of the battery case) to the voltage regulator or starter, depending on your vehicle. Take your time to insure you are tracing the correct cable, as the cable may be sheathed with other wiring.
Loosen the cable at the positive battery terminal with an adjustable wrench turned in a counterclockwise direction. Loosen the cable at the other end in the same fashion. Keep all fasteners for the installation of the new cable.
Note the position of any cable ties or electrical tape that hold the cable in place. Cut the ties or tape very carefully with a utility knife. Note how the cable is routed before removing it.
Remove the positive cable from the engine compartment. Pull the cable out of the plastic sheathing (which is usually split on one side for this purpose) if necessary.
Compare the new positive cable to the old cable to insure it is the same length, thickness, and has the same connectors and fittings on each end as the old cable. Place the new cable into the sheathing through the split opening (the sheathing will snap back around the cable) and route the cable exactly as the original. Replace any cable ties and electrical tape to hold the cable in place.
Connect the positive cable to the voltage regulator or starter using the original fittings tightened in a clockwise direction with an adjustable wrench. Connect the other end of the cable to the positive battery terminal. Push the negative battery cable onto the negative battery terminal. Tighten both terminals with an adjustable wrench in a clockwise direction. Close the hood.
