Why is My ADT Motion Sensor Blinking Red?

Hi all…

I recently installed an ADT motion sensor in my home, and I’ve noticed that it occasionally blinks red. I’m not sure what this means and whether it’s something I should be concerned about. The sensor seems to be working fine otherwise, but the red light has me a bit worried.

Here are some details that might help:

  • The sensor is installed in the living room.
  • It blinks red when there is movement in the room.
  • The system is armed in “Stay” mode most of the time.

Does anyone know what this red blinking light indicates? Is it a sign of a malfunction, or is it just normal behavior? Any insights or suggestions would be greatly appreciated… TIA


Your ADT motion sensor may be blinking red because either Low Battery, One of the most common reasons for a red blinking light is that the sensor’s battery is low and needs to be replaced, to show tamper Alert, the sensor might have been tampered with or the cover might not be properly secured. This can trigger a tamper alert which often causes the light to blink red.

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Hi people, one of the most common reasons for a motion sensor to blink red is a low battery, If the sensor is battery-powered, the red light may be signaling that it’s time to replace the batteries. Some ADT motion sensors have a red light that blinks when they detect motion and this is often seen during a walk test mode or when the system is disarmed to show that the sensor is working properly. Again, blinking red light can sometimes indicate a fault or malfunction with the sensor and this could be due to internal issues or connectivity problems with the control panel.