Look for small led lights on the sensors.
Garage door sensor red light.
Each sensor will usually have a light.
A common cause of a malfunctioning garage door sensor is lack of power supply.
To unlock your garage door opener push the lock button for 5 seconds.
The transmitters remotes will not work to close the garage door.
These sensors are little black boxes found on either side of the bottom of the garage door.
The red light on the receiving sensor glows bright red when the sensors are aligned properly.
If you notice that any of the leds has a blinking light it is a sign that they need to be aligned to function properly.
If they re turned on in both the sensors then there is no issue with the power supply.
If you find the lights turned off in one or both the sensors it indicates that there is a problem in power supply.
The problem is either due to a blocked path between the sensors dirty eyes loose wires at the sensors or at the motor head or just bad sensors.
Put on the electric power supply and look at each led on both sensors.
The solution might be simpler than you think.
Check out this simple video about how to fix this issue.
Check the sensors leds each of the sensors mounted on the garage door has a led light located at the outer side.
When the infra red sensors are malfunctioning usually one of the sensor lights will be blinking.
Inspect each sensor to make sure the green or red power indicator lights are.
If both the red source and green sensor lights are on and not blinking then the door mechanism is working properly.
Raise the garage door using the control button on the garage wall or the remote control unit from a vehicle.
Perhaps you fear the sensor might be low on batteries or worse nearing the end of its lifespan.
Yellow light instead of red does your garage door sensor have a yellow light that s making you worry.
The good news is a yellow light is your garage door sensor s descending line.
Can t figure out.
If just the red source led is out unplug the mechanism check the wiring and plug it back in.
Is your garage door opener blinking.
One will have a green light used to show that the units are powered up and the other will have a red light to show that there s no obstruction between the sensors and that they re seeing each other.
Linear garage door openers have a green light on the sending sensor and a green and red light on the receiving sensor.
If this doesn t fix your problem then the problem is more than likely the safety reversing sensors.
The green lights let you know there is power going to the sensors.