Charger LED indicates F2 or a temperature warning; battery will not charge or stops charging prematurely.

Safety first: Unplug the charger before moving it. Do not cover the charger during operation.

• Allow cooling or warming: If the battery is warm from recent use, let it rest at room temperature for 1–2 hours before charging. If it is cold, allow it to warm naturally indoors.
• Check charger location: Ensure the charger is in a well‑ventilated area away from direct sunlight, heaters, or very cold drafts.
• Inspect vents: Make sure the charger’s ventilation slots are not blocked by dust or objects.

If F2 persists with a room‑temperature battery and proper ventilation, the battery’s internal temperature sensor or the charger’s sensing circuit may be faulty. Replace the battery first; if the issue remains, replace the charger.