A sensor's status in the ADT+ app can look wrong when it is stale or its state has changed. A door or window sensor that shows open when closed may be misaligned with its magnet; check the two parts sit across the gap. A sensor shown missing or offline follows the offline steps: check the Base, the signal and the battery. The alert icon on the dashboard counts issues preventing full arming, such as an open door, a low battery or a missing sensor, and tapping it lists the troubled devices; the Base LED shows a yellow Disarm button when a device is faulted, lost or low on battery.
After a power outage the Base needs a few minutes to reconnect and status can be stale. Refresh the app and compare with the Base.
The checks in more detail
If the low battery persists after replacing the battery, delete and re-add the sensor. A motion sensor may show quiet for long periods simply because nothing moved, so test by walking across. Time on events follows your phone and location. If status stays wrong, contact ADT chat with a screenshot and the LED pattern. Photograph the app and the Base together so the mismatch is clear. A status that flips is a connection problem. Contact support with screenshots. The number on the alert icon counts issues, so a single device with two issues shows a two, which explains why the count can exceed the number of sensors you see.
Compare the app's list with the Base LED when you are unsure, since the two often show the same fault in different ways and together point at the cause.
Differential
Likely causes of “ADT sensors and detectors shows the wrong time, state or sensor reading”, and how to tell them apart
- 1
Misalignment
What separates it A door or window sensor shows open in the app when the door is closed and the sensor is misaligned
How to confirm Realign the sensor and its magnet so that the two parts sit close together and line up
- 2
A weak battery
What separates it The status in the app is stale and does not change because the sensor's battery is getting weak
How to confirm Replace the battery in the sensor with the right type and check that the status updates
- 3
A missing sensor
What separates it A sensor shows as offline in the app because it has gone missing from the Base
How to confirm Follow the offline steps for the sensor, replacing the battery and re-adding it if needed
- 4
A power outage
What separates it The status looks stale right after a power outage because the Base has not reconnected yet
How to confirm Wait a few minutes for the Base and the sensor to reconnect, then refresh the app
- 5
A quiet sensor
What separates it A motion sensor looks idle in the app because nobody has moved in front of it for some time
How to confirm Test by walking across the sensor's field of view and watching the status change in the app
Before you touch a setting
Record this first — changing settings destroys the evidence
- The status the app shows and what the sensor is really doing
- The alert list and which devices it names
- The Base LED color and pattern
- A screenshot of the wrong status
Try in this order
0 of 7 completedRead the alert icon list
ReversibleRead the alert icon list to see which device the system is reporting a problem with and what the problem is.
Check alignment
ReversibleCheck the alignment of a door or window sensor and its magnet, which should sit close together with a small gap when the door is shut.
Check the battery
ReversibleCheck the battery and replace it if it is low, because a weak battery can leave the status old and unreliable.
Compare with the Base LED
ReversibleCompare the app with the Base LED, where a yellow Disarm button means a device is faulted, lost or low on battery.
Refresh the app
ReversibleRefresh the app so it shows the latest status, since an older screen can show a problem that has already been fixed.
Wait after a power cut
ReversibleWait a few minutes after a power cut before you judge the status, because the Base needs time to reconnect the sensors.
Contact ADT
ReversibleContact ADT with a screenshot if the status stays wrong, so the support team can see what the app is showing.
Model-specific
What is true of this model and not of its siblings
- Status
- Shown on the dashboard and the Base LED.
- Alert icon
- Lists issues blocking arming.
- Other models this page answers
- These steps also fit the Carbon Monoxide Detector, Live Light, Smoke and Carbon Monoxide Detector, Smoke Detector.
Stop boundary
When this stops being a self-service repair
- !If status stays wrong after re-adding, contact ADT through chat
- !If a device is missing, follow the offline article
- !If a battery is low, replace it soon so the sensor keeps reporting correctly
Evidence ledger
Sources behind this answer
Base LED patterns.
Offline meaning and fixes per device.
Battery types and lives.
Motion sensor setup and use.
The company and its products.
Exact questions
Common questions
Why does it say open?+
A sensor can say open because it is misaligned with its magnet or because the door or window really is open, so check both.
What does the alert icon show?+
The alert icon shows the issues that are preventing the system from arming, such as an open sensor or a low battery.
Can status be stale?+
Yes, status can be stale if the sensor or the Base has lost its connection, so refresh the app and check the connection.
Can a quiet motion sensor be normal?+
Yes, a quiet motion sensor can be normal, because it only reports when something moves in its field of view.
How long after an outage?+
It can take a few minutes after an outage for the Base and sensors to reconnect and the status to catch up.
Should I compare with the Base?+
Yes, compare the app with the Base LED, because the two together show whether the fault is with the sensor or the app.
What if the battery message persists?+
If the battery message persists after fitting a new battery, re-add the sensor in the app so that its status is reset.
What is a Live Light?+
A Live Light is a light accessory that works with the Base, so it can be switched on by the system or by a rule.
What is a Trouble beep?+
A Trouble beep is a warning tone that a device has a problem, such as a low battery, and it tells you to look at the trouble list.