Cycling & fitness
Polar s3+ stride sensor battery
1 × 3V lithium coin cell
Polar’s s3+ stride sensor accessory manual lists Battery type: CR2430 (average 200 hours). Coin-twist cover; keep the sealing ring intact. Not CR2450.
How to replace it
| Compartment | Coin-twist battery cover on the sensor |
|---|---|
| How to open | Open the cover by turning counterclockwise to OPEN with a coin. Place the CR2430 in the cover with + facing the cover, reseat the sealing ring, press the cover in, and turn clockwise to CLOSE. |
| Orientation | Positive (+) side facing the cover |
| Access | Coin or simple twist |
| Notes | Replace the sealing ring if damaged. Battery kits with sealing rings are available from Polar retailers/service. |
Important
- CR2430 is thinner than CR2450 — do not substitute CR2450.
- Keep coin cells away from children.
- Sensor must be taught/paired to the Polar training computer after battery work if previously unpaired.
Sources
Helpful for this device
Optional tools for opening, testing or charging — separate from the battery answer.
- iFixit Opening Picks
Non-marring opening for tool-free / clip housings
- Fluke 101 Digital Multimeter
Accurate open-circuit voltage and basic electrical checks
- Digital multimeter
Measure open-circuit voltage and general electronics checks
New battery but still not working?
A fresh 1 × CR2430 should restore Polar s3+ Stride Sensor if the battery was the problem. Work through the checks below before replacing the device.
- Check orientation
Confirm the cell is seated correctly: Positive (+) side facing the cover
- Check the battery type
This device needs 1 × CR2430 (lithium). Rechargeable cells are not supported for this device. Same size does not always mean the same battery.
- Check known model-specific issues
CR2430 is thinner than CR2450 — do not substitute CR2450. Keep coin cells away from children. Sensor must be taught/paired to the Polar training computer after battery work if previously unpaired.
- Confirm the battery itself
For most coin cells, fitting a known-good fresh cell of the correct code is simpler than capacity testing.
- 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.