liftmaster Chamberlain Garage Door Opener Transmitter 300MC Logo
Posted on Mar 03, 2009
Answered by a Fixya Expert

Trustworthy Expert Solutions

At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.

View Our Top Experts

Garage door won't close

The door will open when you push the wall button but when you try to close it - it reverses, reopens and the light flashes 4 times. There is no obstruction (leaves, cob web, etc), the sensors are working and properly aligned and the door looks to be manually closing well. It is a GarageMaster 1/3 hp, which I understand is made by Chamberlain, and came with the house I bought so I don't have a manual and is probably about 12 years old. I appreciate any responses....Thanks Dee

2 Answers

Cesar Quant

Level 2:

An expert who has achieved level 2 by getting 100 points

Hot-Shot:

An expert who has answered 20 questions.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

  • Expert 74 Answers
  • Posted on Mar 09, 2009
Cesar Quant
Expert
Level 2:

An expert who has achieved level 2 by getting 100 points

Hot-Shot:

An expert who has answered 20 questions.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

Joined: Mar 09, 2009
Answers
74
Questions
1
Helped
72300
Points
131

SAME AS ABOVE... AND IF ISNT WORKING TRY TO INCREASE THE DOWN FORCE OF THE GARAGE OPENER 1/4 TURN UNTIL CAN CLOSE IT... AND IF ISNT WORKING STILL MAYBE UR TORSION SPRING OF UR GARAGE DOOR HAS TOO MANY TURNS.. CALL A TECHNICIAN!

Cindy Wells

Level 3:

An expert who has achieved level 3 by getting 1000 points

Superstar:

An expert that got 20 achievements.

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

  • Master 6,688 Answers
  • Posted on Mar 03, 2009
Cindy  Wells
Master
Level 3:

An expert who has achieved level 3 by getting 1000 points

Superstar:

An expert that got 20 achievements.

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Joined: May 31, 2008
Answers
6688
Questions
0
Helped
3532976
Points
21745

Check if there is a shadow being cast onto one of the sensors as the door closes. We've had the rope for manually closing the door cast a shadow in full sun and trigger the "something crossed the beam" safety reverse. (Our temporary solution was to cast a shadow that remained constant from outside the door.)

Similarly check if there are any weeds or grass that are being blown or bent into the opening as the door closes. If there are plants in or near the doorway, trim them or use an herbicide to kill them and then trim the top growth after the plant dies.

Ad

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Garage door closes most of the way, then blinks and reopens

You can adjust the downward sensitivity by turning an adjustment on the opener
0helpful
1answer

Push buttons on remotes won't raise/close lift master mod 81lm

Check to see if the light in the wall control is flashing. If it is press and hold the lock button for 3 seconds.
0helpful
1answer

I have a 3/4 horsepower liftmaster garage door opener, both the remote and the wall button won't close the garage door but both will open the garage door. however, the garage door will close if I hold...

If when closing the door it reverses to the open position and the main light flashes 10 times it is a door sensor problem. Make sure the small light on each sensor is on and not flickering ever so slightly. (check closely) Tweak them a little even though they may seem to be okay. Check for 5vdc between terminals 2 and 3 on the rear of the motor unit. If there is no voltage or if it is greater than 6vdc the logic board is bad.

0helpful
1answer

Garage door will close with the wall pad but when the remove or key pad is used the door reopens. How is this fixed?

If the main light flashes 10 times when the door reverses to the open position it is your door sensors. Make sure they are pointed at one another and the small light on each one is lit and not flickering. Tweak them a bit. If you cannot get both lights to come on you have a bad sensor.
0helpful
1answer

I have Garage Door Opener from Sears. Wall push button & the the remote from my car open the door OK , but it does not close the door from my car (which is programmed) Wall push button close the door...

If the main light flashes 10 times when the door reverses to the open position it is a door sensor problem. Make sure the sensors are pointed at one another and the small light on each one is lit and not flickering. Tweak them a bit. If you cannot get both lights to come on you have bad sensors.
0helpful
1answer

Craftsman 53918 - 3/4 hp, belt drive garage door opener. Wall unit says safety sensors misaligned. Replaced them as suggested by manual, no fix. Does not appear to be any power from where you plug...

The main light flashing 10 times is the sign of a door sensor problem. Check to see if the small light on each sensors is lit and not flickering. If you cannot get both lights to come on your sensors or the wiring to them is bad.
3helpful
1answer

After a lightning storm, my LIftmaster Formula 1 garage door opener will not close without continually holding down the garage door button on the wall. If you push the button once and then let go it will...

If when the door reverses the main light flashes 10 times you have a problem with the door sensors. Make sure they are pointed at one another and the small light on each one is lit and not flickering. They must be pointed at one another for both lights to be on. If you cannot get the lights to come on you have a bad logic board.
0helpful
1answer

Craftsman LiftMaster Chamberlain Garage Door Opener Wireless Keypad Model 976LM Security+: My craftsman 1/2 hp garage dood does not close whe...

If the main light flashes 10 times when you try to close the door it is a sensor problem. Make sure they are not flickering ever so slightly and that they are not loose on their brackets. Tweak them a little bit.
0helpful
1answer

What do 4 flashing lights mean on craftsman door

4 FLASHES
Safety reversing sensors slightly misaligned (dim or flashing LED).
1helpful
2answers

Garage door opened, won't close

If you can press and hold the wall button and the door will go down, you have a photo eye issue. Check the photo eyes at the bottom of the door.
Not finding what you are looking for?

602 views

Ask a Question

Usually answered in minutes!

Top liftmaster Electrical Supplies Experts

Cindy Wells

Level 3 Expert

6688 Answers

ADMIN Andrew
ADMIN Andrew

Level 3 Expert

66967 Answers

Steve Pack
Steve Pack

Level 3 Expert

7128 Answers

Are you a liftmaster Electrical Supply Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...