Sears Garage Door Opener question

[velomont]

We have a Sears 1/2 HP electric garage door opener. It comes with a remote monitor which indicates whether the door is open or closed (green light=closed, red light=open). For the last few weeks we've noticed at night that the monitor lights are alternating between the red and green. I then go to the garage to confirm that all is secure and the door is closed.

I can't find our manual and any online manuals don't seem to mention this. I have one concern that this indicates that someone is driving around with a remote and randomly trying to open garage doors but that's just an unsubstantiated theory.

Are any of you familiar with this?

Thank you very much

[Francis Vaughan]

Before getting at all worried I would be inclined to replace the batteries in the monitor. Weird behaviour like this is often nothing more than a symptom of marginal battery voltage. If it is mains controlled, I would be more concerned that it has simply become faulty.

Modern garage door systems have a pretty secure coding system, and whilst it is possible to break, typically by recording the output of a remote and retransmitting it, the old days of all the door openers obeying the same signal are long gone.

[thelabdude]

Yes, when in doubt, replace the batteries. How does the monitor know the door is closed? Does it rely on the switch that tell the drive not to reverse because the door is closed or does it have another switch? Look forf a separate switch and check it.

[johnpost]

if the monitor was responding to attempts to open the door you might also see indicator lights or the illumination light on the unit come on momentarily or the unit make a noise. batteries in the monitor or the switch in the opener that provides the signal to the monitor would be the two things to look at,

[FoundWaldo]

We've had a couple of those monitor things and we found them to be really flaky. Yes, the batteries would be the first thing I'd try, but both of the ones we had failed with similar symptoms.

[Lare]

On the monitor I have, alternating red and green lights mean the monitor sender and receiver have lost communication.

Sometimes I can fix it by opening and closing the door, but I think that changing the batteries is the best bet.

[Magiver]

the door opener is probably a rolling code unit (the code changes each time) It's not impossible to open them but I'd be surprised if it happens regularly.