A careless or rushed parking job can cause the car s bumper to block the sensor.
Residential garage door goes down but goes back up unexpectedly.
It all depends on the configuration but you likely have a button that activates the door operator.
It goes partway down reverses direction and goes back up again.
When that happens the distance your garage door needs to travel may change.
Garage doors have many parts that all work together including safety features.
But when the door begins to descend all on its own the problem may point to the opener s logic board or the circuitry inside the motor unit itself.
Your garage door sensor works by having two photo sensitive devices on either side of the garage door.
Your limit switch needs to be adjusted.
Find local garage door repair.
You push the button to close the garage door.
These garage doors have sensors near the ground to ensure nothing gets stuck underneath the door when it closes.
If the door goes up seemingly on its own after you close the door be sure to check for any debris the sensor is picking up.
The button can easily get dirty and stuck in the pushed position.
This is almost always the result of a dirty or obstructed safety feature.
But changes in weather conditions can causes your garage door components to shift or contract.
If these can t see each other when the door is almost shut it will send a signal to the garage door motor to open back up.
Examine the garage door opener button.
In cases like this your travel down setting simply needs to be adjusted to the new distance.
The door operator button is similar to a door bell.