The battery should be checked every three to six months by a qualified service technician for incorrect fluid level and signs of corrosion at the terminals. The cables, terminals and battery top should be cleaned if they look dirty or corroded.
Some batteries are equipped with removable pods or vent caps so that the electrolyte levels in each cell can be checked and filled with water if the level is low. Always use distilled water to fill the battery in order to prevent chemicals from contaminating the battery. Be careful not to overfill the vent wells. The fluid should cover the lead plates in the battery and be no higher than 1/8 inch from the bottom of the vent well. If your vehicle has not been driven for an extended period of time, the battery should be recharged before use.
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