Tuesday, February 14, 2017

Stopping the Liftmaster 888LM MyQ Control Panel's Warning Beep

So I have this cool garage door opener, a Liftmaster 8500 with a MyQ 828LM Internet gateway, that can be controlled remotely over the Internet.
But it the 888LM MyQ Control Panel makes a horrendous warning beep when you close the door via Internet app:

It is just like a fire alarm! Really loud. I guess the idea is that if you are not home and you close the door remotely, they want to warn anyone nearby the door is going to close. So it blasts this warning beep for a full 10 seconds before closing and then continues to beep until the door is closed. I did it once at night and I was concerned I would wake the neighbors! (Note the beep doesn't happen if you use the regular garage door remote or the wall button.)
Personally, I figure the other safeties that are built into the garage door (like the photo eyes) are enough protection. But you must decide about the risk of disabling the beep yourself! The garage door is potentially dangerous, and you should keep every safety device. Make any changes at your own risk!
I decided to find a way to disable the beeping. A bit of googling and I found many people complaining about the problem and I must thank Philbin Adamsworthy for the inspiration for this project.

On my door the warning beep comes from the wall mounted button, the 888LM, that operates the door from inside the garage:

There is a screw under the flip up button, I removed that and then you have to slide up the unit to remove it from a second screw that is hidden underneath:

There are wires attached to the back that need to be removed to to take the LM888 off of the wall:

There is a thin black cardboard insulating back on the unit, that is held in place by two posts on the back of the unit.

I lifted the cardboard from the bottom and then carefully pried the cardboard free from those posts with a small screwdriver:

Even after you remove the two screws for the wires, the circuit board is held in place at four points along the side of the plastic housing. I used a large screwdriver to lever the housing away from the circuit board at each of the four points and popped it free:

Next I lifted the top of the circuit board and carefully wiggled it free and slid it toward the top and up to remove it:

Flipping the circuit board over you can see the buttons that fit carefully into the cover. Note there are rubber buttons and a guide that can fall out of the housing. I was careful to note their original positions.

Here is the delicate part. I used a small screwdriver to carefully lever the top off of the speaker housing. If you put the screwdriver too far under the housing you will damage the speaker's internal board; the screwdriver needs to just barely go under the edge.

Underneath are two fine wires to the speaker. I snipped those.

And then I removed the speaker and discarded it!

When installing the board back into the housing I was careful the sensor fit into the plastic guide properly. This guide does come out of the housing, so you do want it positioned correctly:

The circuit board slides back into the housing and snaps back in. I was careful the LEDs and buttons lined up.

And then I replaced the cardboard, pushing it down over the two posts to attach it. And I replaced the screws, leaving them loose enough to reinstall the wires on the wall. Note the screws are marked for the wires, Red and White.

And that was that. I put it back up on the wall and the annoying warning beep was gone!