Most vehicles use 12-volt batteries to start the engine and power the accessories while the engine is running. The vehicle's alternator, generator or magneto keeps the battery charged so that it is at full capacity the next time you need to start your engine. Sometimes the battery will drain if the vehicle has not been run for several days. In this case, you might need to charge the battery with a battery charger before it will turn your engine over.
Open the hood or battery compartment of your vehicle.
Turn your battery charger off if it has a power switch. Make sure the power cord is unplugged.
Squeeze the handles of the alligator clip at the end of the negative (black) battery charger cable to open the jaws and place it over a heavy part of the vehicle's frame. Release the clip so that the spring tension in the clip will hold the cable firmly to the frame.
Connect the positive (red) battery charger cable to the positive battery terminal in the same fashion. Plug the battery charger power cord into an electrical outlet. Turn the battery charger on.
Make sure the voltage setting (if equipped) on your charger is set to 12 volts.
Check your battery charger's voltage gauge frequently. Turn the charger off when the gauge reads 12 to 14 volts.
Unplug the charger from the wall outlet. Disconnect the negative charger cable first, then the positive cable by squeezing the alligator clip handles. Close the vehicle's hood or battery compartment.
