How to Fix / Troubleshooting

Safety first: Unplug the opener. Do not place hands near sprockets or moving parts while power is connected.

Steps to diagnose and repair:

Inspect chain or belt: Look at the Motorlift rail. If the chain or belt is hanging loose or broken, it must be re-tensioned or replaced.
Check trolley movement: With the door disconnected, slide the trolley along the rail by hand. It should move freely. If it binds, inspect for bent rail or damaged trolley and replace as needed.
Open the motor housing: Remove the cover and inspect the main drive gear (often a white nylon gear). If teeth are worn or missing, the gear is stripped.
Replace gear and sprocket kit: Order a Motorlift gear and sprocket kit. Disassemble the old gear assembly, clean out debris, and install the new gear and grease as directed.
Reassemble and test: Reinstall the cover, tension the chain or belt to manufacturer specs, and test door operation.

Motorlift opener display shows E4; motor hums but door does not move or moves only slightly.

Possible Causes