How to Fix / Troubleshooting

Safety first: Disconnect power and ensure the door is supported before working on the drive system.

Check manual release: Verify the red cord or release lever is returned fully to the engaged position. On some Nice models, the carriage must be moved until it re‑locks with the trolley.
Inspect chain/belt: Look along the rail for a broken or hanging chain/belt. If broken, do not operate the motor until the drive is replaced and the door is secured.
Examine carriage and sprockets: Check the trolley/carriage teeth and the motor sprocket for wear or stripping. Replace any worn components.
Check coupling: On shaft‑drive Nice operators, ensure the motor shaft coupling to the door shaft is tight and not sheared.
Test after repair: Re‑engage the drive, restore power, and run a full cycle. If E12 persists with a solid mechanical connection, the control board's drive monitoring circuit may be faulty.

Nice opener shows E12 and the motor runs briefly then stops with no door movement.

Possible Causes