Nice opener shows E14 and the door opens partially then stops, often accompanied by beeps or flashing.

Safety first: Disconnect mains power before handling the battery. Batteries can leak or vent.

• Locate the battery: On Nice models with backup, the battery is usually inside the operator housing or in an external battery box. Open the cover and visually inspect for swelling, leaks, or corrosion.
• Check connections: Ensure the battery plug is fully seated and the terminals are clean. Clean light corrosion with a baking soda solution and dry thoroughly.
• Measure voltage: Use a multimeter to measure battery voltage. If it is significantly below the rated voltage (e.g., under 11 V for a 12 V battery), replacement is recommended.
• Replace battery: Install a new, Nice‑approved battery of the same type and capacity. Observe polarity when connecting.
• Test charging: Restore mains power and verify that the battery voltage slowly rises, indicating the charger is working. If E14 persists with a new battery, the charger circuit on the board may be defective.