I have a Liftmaster Prof. 1/3 H.P. I close the garage with the garage door clicker, but when I come home hours later the garage door is OPEN. Please advise.

Check the antenna on the motor. It is usually a single thin wire. There also could be something nearby that is causing interference to the unit and it wont pick up the signal till the transmitter is close enough to overpower the interference.

Contact the manufacturer with your problem ON LINE. They might be able to help you.

Have your neighbor bring over his remote and open or close your door with it. Then hold the smart/learn button in for 6 seconds on your opener. Then see if he can open your door. He shouldn't be able to because that procedure erases the memory in your opener. No remotes should work. You need to get that remote #53778 back and program it and then see if your neighbor can open your door. If he can open your door at any point after you have held that button in for 6 seconds you need to get a new door opener.

If the door starts to close and then the main lights flash 10 times and the door reverses to the open position you have a door sensor problem. Make sure they are pointed at one another and the small light on each one is lit and not flickering. Tweak them a bit.

Have you tried adjusting the antenna position? If you can't find a good position for the antenna, you may want to extend it and bring it close to or outside the garage door opening.

On the rear of the motor unit near where all those white wires go you will find the smart/learn button. Press and hold the button on your clicker while you press and immediately release the smart/learn button. Should do the trick.

I have a feeling your neighbor operated their door opener when you were programming your new clicker. Try erasing the memory of your opener and then program the clicker again making sure your neighbors do not operate theirs at the same time. To erase the memory hold the smart/learn button in for 10 seconds.

The Security+ system is a rolling code system and is digital, so it will work with the Homelink in vehicles and with the remote control units that come with the opener. Also with new remotes that are purchased specifically for that opener. Your "clickers" require specific instructions and you need to use the Smart Learn function in order to use them with this opener. In addition, check the Brand Switch settings to be sure they apply to your opener, and the correct Smart Button color on the opener. Read carefully to determine whether you need to set ANY dip switches at all or can you just set them all to off depending on your opener? Check the instructions carefully. Here's a link to the page where you can download a copy of the Clicker instructions if you don't already have it:
. Clicker Model CLT1D Remote Control Owner Manual

no relation. did you plug rpm sensor and logic board connectors on well.

problem is in eyes. are they clean. aligned . led on each is lit. aligned. that is your problem. they rarely go bad.