SimpliSafe's battery article lists each device: the Entry Sensor takes one Duracell CR2032 lithium cell with a life of up to five years; the Motion Sensor Gen 2 takes one CR123A cell for up to four years; the Glassbreak Sensor one CR123A for up to three years; the Smoke and CO Detector two CR123A cells for up to two years; the Smoke Detector one CR123A for up to five years; the Carbon Monoxide Detector three AA lithium cells;
The checks in more detail
the Keypad four AA alkaline cells for eight to twelve months; the Extra Siren four AA alkaline cells for up to one year, needing a Phillips-head screwdriver for its cover; and the Panic Button one CR2032 for up to five years. The Key Fob battery cannot be replaced. When a sensor needs new batteries the system shows an error on the Keypad. To change a battery, slide most sensors up and off their brackets, replace the cell and refit.
If a Keypad's batteries die quickly, SimpliSafe advises enabling Power Savings mode, which turns off the proximity sensor: Menu, Master PIN, Devices, choose the Keypad, Power Savings. Wait at least three minutes before inserting new Keypad batteries. Use the named brands where listed. If a sensor does not return after a battery change, remove and re-add it in the app. Write the fitting date on the inside of the battery cover so that you know the age at the next warning.
Cold garages and hot attics shorten battery life, so expect earlier warnings there. Keep spare batteries of each type in one labeled box. A battery that dies within weeks usually means a cause such as constant triggering or a marginal signal, so find the cause instead of replacing batteries repeatedly. SimpliSafe lists lives from one year for the Extra Siren to five years for the Entry Sensor, so a warning roughly on schedule is normal and a warning far early is worth investigating.
Differential
Likely causes of “SimpliSafe sensors, Keypad and accessories has power or battery problems”, and how to tell them apart
- 1
An old battery
What separates it The Keypad shows a low battery warning because the battery in the device is old
How to confirm Replace the battery in the device named on the Keypad with a new one of the listed type
- 2
The wrong cell
What separates it The device will not power on because the wrong type of cell has been fitted
How to confirm Use the type listed for that device, such as a CR2032 for the Entry Sensor or a CR123A for the Motion Sensor
- 3
Heavy Keypad use
What separates it The Keypad batteries die quickly because it gets heavy use and its proximity sensor is always on
How to confirm Enable Power Savings on the Keypad, which turns off the proximity sensor to save battery
- 4
A long-offline sensor
What separates it The sensor does not return after a battery change because its link to the Base Station was lost
How to confirm Remove the sensor in the app and add it again so that it links with the Base Station afresh
- 5
Cold or heat
What separates it The battery life is short because the device sits in a place that is very cold or hot
How to confirm Move the device away from extreme heat or cold, since these conditions shorten battery life
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which device it is and the type of battery it takes
- How old the battery in the device is
- The exact message shown on the Keypad
- Whether Power Savings is turned on for the Keypad
Try in this order
0 of 7 completedRead the Keypad error
ReversibleRead the Keypad error to see which device needs a battery, since it names the device in question.
Slide the sensor off its bracket
ReversibleSlide the sensor off its bracket and open the cover, taking care not to damage the battery contacts.
Fit the listed battery
ReversibleFit the listed battery with the correct polarity, matching the plus and minus marks inside the cover.
Wait three minutes for the Keypad
ReversibleWait at least three minutes for the Keypad before fitting new batteries, as SimpliSafe advises.
Enable Power Savings
ReversibleEnable Power Savings on the Keypad, which turns off the proximity sensor and so extends battery life.
Remove and re-add if needed
ReversibleRemove and re-add the sensor in the app if it does not come back, to build a fresh link to the Base Station.
Contact SimpliSafe
ReversibleContact SimpliSafe if the device stays dead after a new battery, and tell them the device and battery type.
Model-specific
What is true of this model and not of its siblings
- Coin cells
- Entry Sensor and Panic Button use CR2032.
- AA cells
- Keypad and Extra Siren use AA batteries.
- Other models this page answers
- These steps also fit models Entry Sensor, Extra Siren, Glassbreak Sensor, Wireless Keypad, Panic Button, Temperature Sensor, Water Sensor, Key Fob.
Stop boundary
When this stops being a self-service repair
- !If a fresh battery does not help, contact SimpliSafe support
- !If the Key Fob will not work with a new battery, contact SimpliSafe support
- !If life is very short, check interference and placement
Evidence ledger
Sources behind this answer
Battery types and lives for every device.
Entry Sensor battery.
Keypad power saving.
Battery and range steps.
The company and its products.
Exact questions
Common questions
What does the Entry Sensor use?+
The Entry Sensor uses one CR2032 lithium cell, which is designed to last for up to five years.
How long do Keypad batteries last?+
Keypad batteries last about eight to twelve months, depending on how much the Keypad is used.
What does the Extra Siren use?+
The Extra Siren uses four AA alkaline cells, which are fitted inside its case.
What does Power Savings do?+
Power Savings turns off the Keypad's proximity sensor, so it wakes less often and saves battery.
How long to wait for the Keypad?+
Wait at least three minutes for the Keypad, before you put in new batteries after taking the old ones out.
Do I need a screwdriver for the Siren?+
Yes, you need a Phillips screwdriver to open the Siren, where the battery cover is held by a screw.
How far can the Motion Sensor detect?+
The Motion Sensor detects movement up to 35 feet away in a 90-degree field of view.
What is Pet Mode?+
Pet Mode is a Gen 2 motion setting that helps the sensor tell pets from people, so pets do not trigger it.
How far apart should Keypad and Base Station be?+
Keep the Keypad within about ten feet of the Base Station if possible, so that the two can communicate reliably.
What does Keypad Out of Range mean?+
Keypad Out of Range means the Keypad is not communicating with the Base Station, so move them closer together.
Can the Key Fob battery be replaced?+
No, the Key Fob's battery cannot be replaced, so the fob is replaced when the battery is used up.