Door sensor not always showing close

We had a false alarm related to a door sensor. For some reason, it’s a little flaky when arming. Sometimes I have to tap lightly on the sensor in order for it to show closed. Last night, it opened and triggered a false alarm. Let me know if you have any advice.

Some questions to try to hone in on what may be going on: Is this a 2GIG thin door/window sensor? When you say you have to tap on it are you physically moving the sensor closer to the magnet? What material is the door? And has this just started or has the sensor always behaved this way?

Hi Amanda,

Yes, it’s a 2GIG thin door/window sensor. No, we aren’t physically moving it. Just tapping on the sensor a couple times seems to bring it back to closed/ready to arm.

It’s a wood door. The sensor has been working flawlessly for the last 14 months and just started experiencing the issue. It’s happened about 3 - 4 times over the last couple weeks.

Thanks in advance for your help!


The mechanism that makes the sensor open and close is a magnetic reed switch. If you take the circuit board out of the white plastic case you can actually see it on the bottom side of the circuit board in a skinny little glass tube on the side of the sensor where the outer plastic has 3 lines. I don’t recommend taking it out though as it’s very difficult to do without breaking the sensor. I’ve broken plenty of sensors doing that. In fact, it looks like tomorrow morning I’ll replacing my front door sensor. Curiosity killed that cat.

Reed Switch

If tapping the sensor fixes your problem then my guess is that the reed switch is sticking or loose or something of that sort. I don’t know of a way to fix it. It probably needs replaced.