My liftmaster 1345 garage door opener does not work; I replaced the logic board and got the wall mount to work but not the remote; I replaced it and still no good

Logic board.

Did you program the opener after replacing the logic board? Press and hold the button on the remote while you press and immediately release the smart/learn button on the logic board.

Sounds like a logic board problem. Remember the wall switch is hard wired and doesn't use the receiver which is part of the logic board.

I would remove the logic board and check for loose or missing traces on the logic board.

Your receiver has quit working. It is part of the logic board. The part number for the logic board is on the end of the opener where all the white wires go. It starts with 41A.

I have the very same problem. I have 2 Liftmaster 2500, 1/2HP openers installed in a 2 car garage. They are merely 15 feet apart in my garage ceiling. About 15months ago one stopped working by only the remotes. Went through the process of reprogramming the good one 1st and replaced batteries in the remotes, then trying to reprogram the one not working. Checked for radio interference near the one not working no LED or Halogen Lights, no wall tarnsformers, no cell phone interference etc... Nothing worked to on the 2nd
opener in trying to get the remotes working again.
I then purchased a New Logic Board, part number 41A5507-B. It was about $70 and then installed it in the 2nd opener which is not working. Tried to get the remotes programed - still nothing? I was baffled. I called Liftmaster - the only suggestion they gave me was was to totally unplug the GOOD opener and try the reprogramming up close to the 2nd door opener that's not been working. SURE enough - the Opener Remotes "Learned" okay and started working! Liftmaster Help line indicated that the thought to be GOOD opener actual had the defective Logic board and it was over powering the signal from the 2nd opener which was not working. I'll be taking the New Logic board and replacing it in the 1st opener.
Thank you Liftmaster for the help !

Your wall control is hard wired and doesn't use the receiver portion of the logic board. The remotes do. Your receiver is going bad.

That number you are giving is the part number for the logic board and if you cannot program your remotes is the part you will need. It is expensive.

Check the wiring going to the sensors to make sure it is not broken or disconnected. You have a problem with the sensors themselves or the logic board. Unfortunately the only way to be sure is to replace.

meerkat1 your receiver has quit working which is part of the logic board. The logic board runs around $80.00 for the part alone. Might be time to get a new opener.