About this replacement
TomTom One XL / XL 325 — 3.7V Li-ion Replacement Battery (F724035958)
This 3.7V 800mAh Li-ion cell replaces the internal battery in the TomTom One XL, XL 325, Edinburgh, and One 3rd Edition portable GPS navigators. It restores power to the touchscreen, processor, and GPS receiver when the original cell no longer holds a charge. Dimensions are 44.30 × 34.10 × 5.00mm — measure your existing cell before fitting if you are unsure.
- One XL and XL 325 platform compatibility: These models share the same battery bay dimensions, connector pinout, and voltage rail. The One 3rd Edition and Edinburgh variant use the same cell under different regional SKUs. One cell covers all four.
- Bench tested on actual hardware: We ran this cell against the OEM part numbers F724035958, F702019386, and Quanta VF9. The BMS handshake completed on first connect, charge acceptance was normal, and no fault codes were triggered during discharge cycling.
- Cold-start satellite acquisition after fitting: After installing this cell, power the unit on outdoors with a clear view of the sky. The GPS receiver performs a full cold start after any complete power loss — first satellite fix can take 5 to 10 minutes. Subsequent warm starts drop to under a minute once almanac data is cached.
GPS accuracy reduced when battery charge drops below 20%
The TomTom One XL scales back GPS receiver sensitivity as the cell voltage falls toward the low-voltage cutoff. This is a firmware-level power saving measure, not a hardware fault. Users notice position drift or slower route recalculation in the final charge segment. Keeping the unit on a car charger during active navigation eliminates this behaviour entirely.
Device shuts off without warning before the battery indicator reaches empty
After a full battery swap, the fuel gauge calibration in the One XL is reset. The shut-off voltage threshold can trigger before the on-screen indicator shows low battery, because the device has no accurate state-of-charge history for the new cell. Run two or three full charge-discharge cycles on the new battery to let the firmware recalibrate the indicator. After that, the low-battery warning should appear at approximately 3.5V before shutdown.