Situation: An approximately 15-year-old name-brand chain type garage door opener. The drive train was replaced by myself a couple of years ago, which is unrelated to the problem at hand.
It suddenly started working (from the remote) only to OPEN the door, and not to close it. The wall pushbutton switch always worked. I noticed that if the door was left open for some minutes, it would "recover" and would work again from the remote.
Anyone here can figure this out? Hint: I (much) later recalled replacing the lights in it (one had burned out).
Best regards, Spehro Pefhany