There are two reasons for this kind of malfunction on a liftmaster for Craftsman garage door opener. The first and most simple way to diagnose this problem is to make sure that your opener does not have the remote lock turned on. You can only access this function if you have the correct wall control or wall button that has the lock button right on it if you have a doorbell button for your garage door opener than you can not use this function on your garage door. So this means that there is no way to lock out the remote with just a doorbell type button you would have to have a wall control. And the easiest way to determine if the remote lock is on is to look at the wall button and the green light will be flashing. All you have to do is hold it down for a second or two to lock out or unlock the remote so sometimes people will hit this button by accident and lock out their remotes and not even know it.

hire a garage door technician to replace any control boards

The other simple way to solve this problem is to make sure that you have good batteries in your garage door remotes. Ok now the other more complicated aspect of this malfunction is the receiver board in your garage door opener this is part of the control board that controls all the functions in your opener and it is pretty easy to replace on Liftmaster and craftsmen openers so the only problem you would have is finding a receiver board or a control board because on liftmaster craftsman the receiver board is built into the whole control board. Unlike Genie garage door openers, especially the older ones the receiver board is totally separate from the control board and they are also easy to find and easy to replace. If you have more than one remote and both are not working then it is almost impossible for both remotes to stop working at the same time. If you are not mechanically inclined then you should probably hire a garage door technician to replace any control boards or receiver boards in your opener because you really have to be careful handling them because just a little bit of static electricity from your fingers can make them useless instantly.

replace control boards

If you do decide to replace any control boards or receive a boy just self then you will absolutely find instructions on the Internet. Last thing always remember to unplug your opener before installing any control boards in your opener – If you don’t, it can short out everything that is sensitive to power surges immediately plus its just the safest thing to do since I have been shocked so many times. I have even been shocked after I have unplugged the unit. This is because electricity can still exist after the unit has been unplugged. Anytime you are dealing with digital control boards you should wear rubber soled shoes and touching a piece of metal to release any static electricity would be a good idea.