- 1). Purchase a bottle of distilled water. A bottle of distilled water doesn't cost much, and using this type of water will prevent you from damaging your battery.
- 2). Take the cap off the fluid intake area on your battery. This is a very small cap and is located on the top part of the battery.
- 3). Place the funnel in the hole where you removed the cap. Add water slowly up to the "Max" line. Don't overfill your battery, as doing so can cause the battery to leak and be damaged.
- 4). Remove the funnel and put the cap back on the battery.
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