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Ask Eric M. Bright Your Own Question
Eric M. Bright
Eric M. Bright, We Don't Comprehend the Word Can't!
Category: Home Improvement
Satisfied Customers: 1923
Experience:  I've been been doing things for my clients that others have said cant be done for over a 1/4 Century
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Home Improvement

My lift master 1/3 hp garage door will not close sometimes

and blinks 9 times. What... Show More
and blinks 9 times. What does that mean?
Submitted: 5 years ago.
Category: Home Improvement
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Daniel, Electrical Engineer
Satisfied Customers: 7897
Experience: Expert in electrical & mechanical design, troubleshooting, and problem solving
replied 5 years ago.

Silicon Savant :

Hi there happy to help.

Silicon Savant :

does the door reverse and go back up?

Silicon Savant :

do you have a button in the garage for the door separate from the remotes?

Silicon Savant :

What happens when you hold this down?

Silicon Savant :

let me know,

JACUSTOMER-h2ees2q5- : Yes, the door reverses and goes back up. I have a button in the garage, but that will not work either. I have to manually pull the cable to get the door down.
Silicon Savant :


Silicon Savant :

I believe you have a problem with your alignment sensors here.

Silicon Savant :

They are either loose and coming out of alignment or out of alignment all together.

Silicon Savant :

You should have a solid LED lit on each sensor. Make sure they are aligned and secure and nyou should be back in business.

Silicon Savant :

Hope this helps,
If this answer helped you please click the ACCEPT button.
Positive feedback/tips appreciated!
Have a great day.

JACUSTOMER-h2ees2q5- : The problem happens a lot in the morning. I'll take a look.
JACUSTOMER-h2ees2q5- : Does the light sensor color matter?
JACUSTOMER-h2ees2q5- : One is green. One is yellow
JACUSTOMER-h2ees2q5- : They are in tight. Not loose
Silicon Savant :

yes are they solid?

JACUSTOMER-h2ees2q5- : Yes , solid . No blinking
Silicon Savant :

ok are the rails that they are attached to loose at all?

JACUSTOMER-h2ees2q5- : Fyi I have chamberlain brand opener.
JACUSTOMER-h2ees2q5- : No
JACUSTOMER-h2ees2q5- : Not loose at all
Silicon Savant :

ok, can you give me the exact model number please?

JACUSTOMER-h2ees2q5- : Any idea wher I find it?
Silicon Savant :

on the back of the opener itself.

Silicon Savant :

also can you tell me what direction your garage door faces?

JACUSTOMER-h2ees2q5- : I see part no, Canada and date info. Is it one of these?
Silicon Savant :

just list the numbers you see.

JACUSTOMER-h2ees2q5- : 41a5021-1e
JACUSTOMER-h2ees2q5- : 102 1499a
JACUSTOMER-h2ees2q5- : 12/00
Silicon Savant :

what direction does the dor face?

JACUSTOMER-h2ees2q5- : Faces north
Silicon Savant :

ok, thanks, it was the first number.

Silicon Savant :

ok, the wall button doesn't work either correct?

Silicon Savant :

even when you hold it down?

JACUSTOMER-h2ees2q5- : Yes
Silicon Savant :

ok, give me a minute.......

Silicon Savant :

ok, go to the back of the opener......

Silicon Savant :

increase the DOWN force adjustment and try again.

Silicon Savant :

let me know,

JACUSTOMER-h2ees2q5- : How do I increase down force.
JACUSTOMER-h2ees2q5- : I see. Turn the knob
Silicon Savant :

get a flat head screw driver and turn the down force adjustment screw clockwise.

Silicon Savant :

its on the back of the opener.

JACUSTOMER-h2ees2q5- : Ok, I did it.
Silicon Savant :

try the door now.

JACUSTOMER-h2ees2q5- : My garage door is working, but the problem happens first thing in the morning. I tested it before the adjustment and it went down. I tested it again and it still goes down. I will have to verify in the morning to know if it's fixed.
Silicon Savant :

OK, let me know,

JACUSTOMER-h2ees2q5- : Will do
Silicon Savant :

Please don't forget to ACCEPT if I helped you today.

JACUSTOMER-h2ees2q5- : Thank you
Silicon Savant :

This doesn't mean you can't still respond here if you need further assistance.

JACUSTOMER-h2ees2q5- : I'll let you know if it helped.
JACUSTOMER-h2ees2q5- : My. Problem was not fixed. I still have the garage door re- opening when try to close it.
Eric M. Bright, We Don't Comprehend the Word Can't!
Satisfied Customers: 1923
Experience: I've been been doing things for my clients that others have said cant be done for over a 1/4 Century
replied 5 years ago.

Hi, Welcome to, I am glad you are here! My name is Eric & I will endeavor to answer your question.


When the invisible beam path (safety sensor) is obstructed while the door is closing or if they are misaligned or if a safety sensor is malfunctioning or if there is a break in the wiring, the door will reverse. If the door is not open, it will not close. The opener light will blink 10 times. (Could you have miscounted the blinks? There is no notation in the troubleshooting manual for a light blinking 9 times).


It sounds to me as though the safety sensors are just barely aligned and that the vibration of the closing door is jiggling them just enough to cause misalignment. Try realigning them and or tighten the bolts that hold them in place.


Do you have a copy of your owners manual?

In the event that you do not, Here is a link to a copy of the Liftmaster Professional Security + model 3110 - 1/3 HP manual. Even if your model number is not exactly the same, the procedures described on page 11 to align the safety sensors are the same.

Please refer to page 11 for alignment instructions.


Thanks, Eric