The most important step in Garage Door Opener Troubleshooting is the determination of the wrong parts.
Check the installation of your Garage Door and Garage Door Opener first: they should be installed in such a manner to provide smooth operation of Garage Door Opener.
Any “jumping” of the door and hardware in the first movement, could mean that opener mechanism is pushing or pulling at the wrong angle.
When the door is closed, disconnect the trolley by pulling the manual release rope of the opener, check the door (springs, cables, rollers, brackets), and if everything is fine- move the door by hand to ensure that the door is balanced.
A week spring could mean that the opener is required more forces to lift the weight of the door. All door repairs should be complete prior the opener installation.
The main categories of problems are power issues, wiring problems, components failure and sensors that do not see each other, for whatever reason.
Check the power unit and make sure it’s getting power.
Try different methods to operate a door. Try the inside button, the remotes, and keypad. If one of the remotes work but the button inside doesn’t, it may be a wiring problem. If the wired control works but the remote doesn’t check the battery on the remote transmitter.
Listen for noise when the button pressed. If the unit starts to close but stops and reverses, then it’s most likely a sensor issue.
Check all the wiring from the unit to the sensors, the sensors themselves, make sure that dirt doesn’t obscure sensors lenses, and that they are properly aligned. If all these things check out and they still don’t work, it may be a damaged sensor. It is common, because they’re located near the floor, and are prone to dirt and water damage.
If all else fails, it might be a damaged circuit board in the power unit. These can become non-functional from a power surge, lightning strike or just old age.