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Brian, Architect
Category: Home Improvement
Satisfied Customers: 3123
Experience:  Licensed Architect- 17 years, L.E.E.D. AP
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Liftmaster Formula 1 garage door is not closing completely

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I have a Lift-Master Formula 1 garage door opener. When I push the Open/Close button, it closes for about 1-2 feet and then reverses. I cannot close it except by holding the Open/Close button down until it closes. Same with the remotes. I have to hold them down to close the garage door. It opens fine. I looked at the sensors and one is a constant amber and the other one is green. The green one is solid except when I break the beam, then it goes out. I can detach the door and it opens and closes smoothly with no problems. This just started 3 days ago.

Hi and thanks for using our service!

Sorry to hear about your problem. This is a problem with the safety sensors; either due to a blocked path between the safety sensors, condensation, dirty eyes, loose wires at the sensors or at the motor head, or just misaligned or bad safety sensors. When the invisible beam path is obstructed or misaligned while the door is closing, the door will reverse. If the door is already open, it will not close. The remotes will not work to close the garage door; they can only open it. When this happens, your garage door will only close by holding down on the wall button until the door fully closes. This method is the only way to override the safety sensors and close the door and it is also a direct clue that the sensors are the problem. To correct the problem, you need green indicator lights in both the sending and receiving eyes and they will glow steadily if wiring connections and alignment are correct. The sending eye indicator light will glow regardless of alignment or obstruction. If the indicator light is off, dim or flickering in the receiving eye (and the invisible light beam path is not obstructed), alignment is required. Loosen the sending eye wing nut and re-adjust, aiming directly at the receiving eye. Lock in place. Loosen the receiving eye wing nut and adjust sensor vertically and/ or horizontally until it receives the sender's beam. When the green indicator light glows steadily, tighten the wing nut.

1. If the sending eye indicator light does not glow steadily check for: Electric power to the opener. A short in the white or white/black wires. These can occur under staples or at screw terminal connections. Incorrect wiring between sensors and opener. An open wire (wire break).

2. If the sending eye indicator light glows steadily but the receiving eye indicator light doesn't: Check alignment. Check for an open wire to the receiving eye.

3. If the receiving eye indicator light is dim, realign either sensor. If you cannot get the sensors to light and the wiring is good, you may need new sensors.

If you have any further questions, please feel free to let me know.

Customer: replied 4 years ago.

I'm assuming the sending sensor is the one on the right looking out of the garage. If so, that one is steady amber or yellow. The sensor on the left is green and goes out when I break the beam. That tells me it is receiving a signal from the sensor on the right. I have realigned the sensors and still get the same problem. I have checked the wiring and it is not loose.

Upon further testing, it doesn't always stop and reverse. Three out of 4 times, it will stop and on the fourth try go all the way down. I did this several times.

I still believe you have a sensor problem. The sensors seem to be aligned since they are both solidly lit. You need to look closely at the wiring, to the sensors, to see if it they are broken or pinched by a staple. You can test the wires with an ohm meter for continuity or two wires shorted together. You should have a reading of 4-5v at the sensors. If you have a lower reading and the wires appear to be good, remove the sensor wires from the terminals on the logic board and check for voltage across terminals 2 and 3 on the logic board. If you have 4-5v you will need to replace the sensors. If you don't have 4-5v between terminals 2 and 3 and the opener is plugged in, the logic board is bad.

Customer: replied 4 years ago.

Well I tested the voltage and here's what I got:

Sensors connected: 5.93 V

Sensors disconnected: 6.23 V

So, I don't know if it's the sensors. I did adjust the force downward button up one number from 5 to 6. Now the doors go down all the time.

I read up on that and it says that sometimes weather can cause this issue. I'm in the Denver Metro area and we've been saturated with rain since Wednesday and this problem started on Thursday. Coincidence?

I had a technician come out 2 years to replace my springs and he said everything else looked good. The system is 13 yrs old. Is it time to replace the sensors for due diligence?

Thanks for your help on this and awaiting your response.


If the door closes without having to hold down the wall button then you may have fixed the problem. The voltage sounds fine as long as you are getting a good reading at the sensors. Verify that the eyes of the sensors are wiped clean....sometimes dirt and moisture can effect them especially after the weather you have had.

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