- 1). Turn off the charger. If your charger can do dual voltage output, set the switch on the charger for the proper voltage, six-volts or 12-volts.
- 2). Connect the cable with a red clip (positive) of the battery charger to the positive terminal of the battery -- marked with a + sign. Connect the black clip to the metal frame of the vehicle the battery is in.
- 3). Plug in the battery charger. Turn the switch of the battery charger to "On."
- 4). Check the gauge on the battery charger hourly -- when the needle is in the "Charged" section of the dial, turn off the charger and remove the cables from the battery.
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