Nice opener shows E4 and the motor does not run when a command is given.

Safety first: Disconnect power and do not force the door. A heavy or unbalanced door can cause serious injury.

• Test door balance: Pull the manual release and move the door by hand. It should lift smoothly and stay at mid‑travel. If it slams shut or is very hard to move, the springs or counterbalance system need adjustment by a qualified door technician.
• Inspect tracks and hardware: Look for bent tracks, crushed rollers, or debris in the travel path. Remove obstructions and straighten minor bends. Lubricate rollers and hinges with a suitable garage door lubricant (not grease on tracks).
• Check force/torque settings: On Nice boards, adjust the trimmer potentiometers or menu parameters for motor force/torque within the recommended range. Do not set excessively high to mask a mechanical problem.
• Motor test: With power off, inspect the motor wiring for burns or melted insulation. If available, measure motor winding resistance and compare to Nice specifications. A very low resistance or visible burn marks indicate a shorted motor.
• Reset and test: After correcting mechanical issues and adjusting force, clear the error (power cycle or reset per manual) and run a full cycle. If E4 returns immediately with a free‑moving door, the motor or control board power stage may need replacement.