Smart locks
August Smart Lock Pro battery
4 × 1.5V alkaline cell
August Smart Lock Pro (and 2nd Gen) uses 4× AA alkaline. Replace all four together. Wi-Fi Smart Lock 4th Gen is 2× CR123A — do not mix the answers.
How to replace it
| How to open | Press the August logo at the bottom of the faceplate, remove cover, replace all four AA alkaline cells positive (+) up, reseat faceplate. |
|---|---|
| Orientation | Match polarity markings |
| Low battery indicator | App or device low-battery cues where equipped |
| Notes | August Support: Smart Lock Pro or 2nd Generation uses 4× AA alkaline. Replace all four at once. |
| Access | Tool-free |
Important
- August Support: Smart Lock Pro or 2nd Generation uses 4× AA alkaline. Replace all four at once.
- Do not use rechargeable batteries per August.
- 3rd Generation Smart Lock is also 4× AA (different cover slide). Wi-Fi Smart Lock 4th Gen is 2× CR123A — do not conflate.
- Battery identification only — no lock-bypass guidance.
Sources
Helpful for this device
Optional tools for opening, testing or charging — separate from the battery answer.
- Ansmann Energy Check LCD
Quick household cell check (good / low / replace)
- ZTS Mini-MBT Multi-Battery Tester
More informative state-of-charge style checks across common formats
- Battery tester
Quick good / low / dead check for household cells
New battery but still not working?
A fresh 4 × AA should restore August Smart Lock Pro if the battery was the problem. Work through the checks below before replacing the device.
- Check orientation
Confirm the cell is seated correctly: Match polarity markings
- Check the battery type
This device needs 4 × AA (alkaline). Rechargeable cells are not supported for this device. Same size does not always mean the same battery.
- Check known model-specific issues
August Support: Smart Lock Pro or 2nd Generation uses 4× AA alkaline. Replace all four at once. Do not use rechargeable batteries per August. 3rd Generation Smart Lock is also 4× AA (different cover slide). Wi-Fi Smart Lock 4th Gen is 2× CR123A — do not conflate.
- Confirm the battery itself
If you have a battery tester or multimeter, check the cell. A low open-circuit voltage often means replace; for rechargeable AA/AAA, a capacity test is more informative than voltage alone.
- Still not responding?
If a correct, fresh battery installed properly does not restore the device, the fault may be elsewhere — the device may need service or replacement.
Need to replace the device?
August Smart Lock Pro is still sold new. Only buy another if a fresh battery and the checks above did not help.