Just recently purchased older home. For the first 3 months no problem - just recently GDO opens and closes on its own. There is no pattern just happens whenever. Any thoughts? We do not have an owners manual for our model 13953636SRT.
This is generally caused by a bad wall control or the wiring from the wall control to the opener. You can first of all eliminate the wall control by removing it from the wall and then disconnecting the two wires going to it. Leave it that way for a few days. If the problem persists you can remove those 2 wires from the opener. They sometimes have a staple that has cut through the insulation and shorts the two wires together. They are connected to terminals 1 and 2 on the opener.