The Smart Lock Series 2 is powered by four Duracell AA alkaline batteries and its PIN Pad takes two Duracell CR2450 lithium batteries, both lasting eight to twelve months depending on use, according to SimpliSafe. To change the lock's batteries, slide the battery cover to the right, replace the four AA cells and slide the cover back until it clicks. For the PIN Pad, use the Release Tool from the box, or a SIM card tool or paperclip, pressed into the pinhole on the bottom so the top pops off, replace the two coin cells and press it back until it clicks.
The checks in more detail
If the lock does not come back online after a battery change, it may have been offline too long, so remove it in the app under My System, Device Settings, tap the lock, Remove Device, and add it back. A dead lock battery can leave the door in its last state, and the door keys still work. Use fresh named-brand cells, since weak batteries cause slow locking and offline errors. Keep spares.
The reset article says if no lights appear on reset, check all four batteries are seated or replace them with new Duracell AA batteries. Check the PIN Pad separately if only PIN entry fails. Write the battery change date inside the cover so you know the age at the next warning. Cold weather cuts battery life, so a lock that warns in winter may be fine in spring. Keep spare AA and CR2450 cells in a labeled box.
A lock that locks slowly a few weeks before the battery warning is telling you the cells are weak, so change them at the first slow lock instead of waiting for the alert. SimpliSafe rates both the lock and the PIN Pad at eight to twelve months, and the two batteries wear at different rates, so track them separately and expect the PIN Pad to fail first in a busy household where the code is entered constantly. Buy the named brands SimpliSafe lists, since cheap alkaline cells can sag under the motor's load and produce the same slow locking as flat ones.
Differential
Likely causes of “SimpliSafe Smart Lock Series 2 has power or battery problems”, and how to tell them apart
- 1
Low lock batteries
What separates it The lock is slow or offline because its four AA batteries are running low
How to confirm Replace the four AA cells in the lock with fresh ones, then check that it returns in the app
- 2
Low PIN Pad batteries
What separates it PIN entry fails because the batteries in the PIN Pad are running low
How to confirm Replace the two CR2450 cells in the PIN Pad with fresh lithium batteries
- 3
Mixed old and new
What separates it The lock is unreliable because old and new batteries have been mixed in it
How to confirm Replace all of the cells at the same time, so that they are all the same age and brand
- 4
A long-offline lock
What separates it The lock will not come back online after a long time offline because its link was lost
How to confirm Remove the lock in the app and add it again, so that it links to the Base Station afresh
- 5
Unseated batteries
What separates it The lock shows no lights because the batteries are not seated properly
How to confirm Reseat all four batteries firmly, checking each one faces the right way, and see if the lights return
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which battery is low, the lock's or the PIN Pad's
- How old the batteries in the lock are
- What the PIN Pad does when you press a key
Try in this order
0 of 7 completedSlide the battery cover off
ReversibleSlide the battery cover off the lock, moving it to the right for the Series 2 model.
Replace four AA cells
ReversibleReplace the four AA cells with new ones of a named brand, all at once and the right way round.
Open the PIN Pad
ReversibleOpen the PIN Pad using the Release Tool or a straightened paperclip, following the manual's steps.
Replace two CR2450 cells
ReversibleReplace the two CR2450 cells and press the top back on, listening for it to click into place.
Check the lock returns
ReversibleCheck the lock returns online in the app, and that the PIN Pad wakes up when you press it.
Remove and re-add if needed
ReversibleRemove and add the lock again in the app if it stays offline, using Device Settings.
Contact SimpliSafe
ReversibleContact SimpliSafe if the lock stays dead after fresh batteries, and tell them what the lights do.
Model-specific
What is true of this model and not of its siblings
- Lock
- Four AA cells.
- PIN Pad
- Two CR2450 cells.
Stop boundary
When this stops being a self-service repair
- !If fresh batteries do not help, contact SimpliSafe support
- !If the lock will not calibrate, reset it
- !If the PIN Pad fails, check its cells
Evidence ledger
Sources behind this answer
Lock and PIN Pad batteries.
Range, interference, battery and update steps.
Unpair, power cycle, factory reset, reinstall.
Battery types and lives for every device.
The company and its products.
Exact questions
Common questions
What batteries does the lock use?+
The lock uses four AA alkaline batteries, and SimpliSafe lists a named brand such as Duracell.
Which tool opens the PIN Pad?+
The Release Tool opens the PIN Pad, and a straightened paperclip can also work for the same job.
What if it stays offline?+
If it stays offline after new batteries, remove it in the app and add it again.
Should I replace all cells?+
Yes, replace all of the cells at the same time, since mixing old and new ones gives unreliable results.
How do I reset the lock?+
To reset the lock hold the pairing button for 20 seconds, until the lights confirm the reset.
What do three flashing lights mean?+
Three flashing lights show that the lock has reset itself, and it needs to be added to the system again.
Do lock updates install themselves?+
No, lock updates are installed manually in the app, so check for one now and then.
What causes interference?+
Steel doors, dense walls and wireless devices cause interference between the lock and the Base Station.