Why Does My SimpliSafe Entry Sensor Keep Showing False Opens

Problem Description

Your SimpliSafe entry sensor reports the door or window as opened when it is actually closed and secure.

Why This Happens in Real Homes

False open alerts from SimpliSafe entry sensors are a magnet alignment problem about 80 percent of the time. The sensor has a reed switch inside that closes when the magnet is within about 1.5 inches. If the door or window has settled, warped, or swollen due to humidity, that gap increases and the reed switch flutters between open and closed. Double-sided adhesive also degrades over time — after a couple of years in direct sunlight or humidity the sensor or magnet can shift just enough to cause intermittent false readings. Peel off the old adhesive, clean both surfaces with isopropyl alcohol, and reattach with fresh 3M Command strips. If the sensor is on a vibration-heavy door like a garage entry, the vibration alone can momentarily trip the reed switch.

Symptoms

• Sensor shows open when door is closed
• Random open alerts with no activity
• Alarm triggers from sensor while away
• Sensor status flickers between states
• Multiple false alerts daily

Recognize these? Here's what usually causes it.

Common Causes

• Magnet too far from sensor
• Sensor or magnet shifted position
• Door or window frame warped
• Vibration causing momentary separation
• Low battery affecting sensor accuracy

Tools & Requirements

Step-by-Step Solution

1

Check Sensor-Magnet Gap

The sensor and magnet must be within one-half inch of each other when the door is closed.

2

Verify Alignment

The magnet should align with the sensor indicator mark or the thicker end of the sensor.

3

Secure Loose Mounting

Remove the piece, clean the surface, and apply fresh double-sided mounting tape.

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4

Account for Metal Interference

If mounted on steel, add a 1/8 inch plastic spacer between the magnet and metal surface.

5

Replace the Battery

Check battery status in the app. Replace with a fresh CR-2032 battery if low.

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Quick Solutions

Still having issues? This is usually the deeper cause below.

Need More Help? SimpliSafe Support

Note: The contact information below connects you directly to SimpliSafe's official customer support team, not Trunetto. They can help with warranty claims, device replacements, and advanced technical issues.

How Does SimpliSafe Compare?

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