Try these tips. If one of your neighbors remote controls is inadvertently programmed into your receiver, you door will open when their remote is activated. If this happens you will need to clear out your receiver and reprogram your remote controls. Press and hold the smart/learn button for 6 seconds or until you see the small LED light near the button turn itself off. If the above steps have been followed and the symptoms continue, there may be an electronic short in either the wall control button or the receiver logic board. In this case, remove the wall control wires from terminals 1 and 2 on the motor unit. Should the symptoms persist after the wires are removed, replace the receiver logic board. If the symptoms stop with the wall control wires removed from the motor unit, replace the wall control button, and the wires leading to the wall control button.

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It ssems that it tries to work when the chain is going one way but not reverse.

We had a similar problem and the fix was simply aligning the sensors. It is so easy for them to get bumped out of alignment.