Corrosion is visible on battery terminals and metal parts inside the enclosure.

Safety first: Wear gloves and eye protection when cleaning corrosion.

• Neutralize corrosion: Disconnect battery, then clean affected areas with a baking soda and water solution. Rinse and dry thoroughly.
• Check charger voltage: Ensure Hyundai battery charger output is within spec (around 13.2–13.8 V). Overvoltage can cause excessive gassing.
• Replace battery: If the battery case is cracked or leaking, replace it immediately.
• Protect surfaces: Apply a light coat of anti-corrosion spray or petroleum jelly to battery terminals.