The light and lock buttons on my wall unit for one of my Craftsman garage door opener have no effect, and the door is stuck in the "lock" mode, so I can't use the remote.

I thought it was the wall unit itself, so I swapped the units for the left and right doors. But that didn't help! The same door is STILL stuck in the "lock" mode and I cannot activate the light, but the other door continues to work fine. So I'm sure it's not the wall unit that is at fault.

I know that the light is functional, because when I press the open/close button the door operates fine and the lights turn on.

It seems that somehow the opener itself is ignoring the light and lock commands, but not the open/close commands. Any ideas?