If your opener seems to overrun the switch and just keeps trying to pull the garage door up or down after it reaches the end of travel you might assume that it missed the.
Garage door not connected to chain.
I hope this helps.
Otherwise the solution is to add some links to the chain.
A chain drive garage door usually has two small switches on the top of the unit these are triggered when small rollers attached to the chain ride into the mechanism.
The motor will run but will not move the chain.
This enables the trolley to connect to the carriage.
Just click here to watch the video.
Pull straight down on the emergency release rope once the door is open.
The chain is located in the garage door s pulley bar.
You may be missing that part.
Check the breaker controlling the door opener and reset if it it s tripped.
Raise the garage door fully.
Begin the chain disassembly.
When the cord is pulled the motor is disengaged from the chain.
Remove this nut from the bolt with a socket wrench.
I provided a video to help adjust the chain.
Ensure that the unit is plugged in the door isn t locked and if you are using a remote that the remote has batteries.