TomTom Pro 8000 GPS Replacement Battery 3.7V 1250mAh

TomTom Pro 8000 — 3.7V Li-Polymer Replacement Battery (SIMPLOM420102829)

This 3.7V, 1250mAh Li-Polymer cell replaces the original battery in the TomTom Pro 8000 GPS navigator. The Pro 8000 is a commercial-grade portable navigator used in fleet and logistics operations. When the original cell degrades, this replacement restores the device to working order without a full unit replacement.

• TomTom Pro 8000 fitment: This cell matches the voltage rail, physical dimensions (62 × 37 × 5mm), and connector orientation of the Pro 8000 mainboard. The BMS in these navigators communicates charge state to the display — this cell's protection circuit responds correctly to that handshake.
• Bench tested on actual hardware: We ran this cell through full charge cycles and monitored BMS cutoff behaviour under simulated GPS receiver and display loads. The protection circuit held stable across charge thresholds without false trips.
• First-fix cold start after installation: After fitting this cell, power the unit on outdoors before driving. The Pro 8000 performs a cold start after any full power interruption — first satellite acquisition can take 5–10 minutes. Subsequent warm starts resolve in under a minute once the almanac is cached.

GPS accuracy dropping at low battery on the Pro 8000

The Pro 8000 reduces RF receiver sensitivity when battery voltage falls below a threshold — this cuts power draw but degrades position accuracy. You may notice the route line drifting or the device losing lock in areas that normally work fine. This is not a software fault. Keeping the cell charged above 3.5V prevents the receiver from entering low-power sensitivity mode.

Pro 8000 shutting off without a low-battery warning

After fitting a new cell, the fuel gauge IC needs a full charge-discharge cycle to recalibrate its voltage-to-percentage mapping. Until that cycle completes, the device can hit its actual cutoff voltage before the on-screen indicator shows a warning. Charge the unit to 100%, use it on active navigation until it shuts off naturally, then charge again fully — one cycle is enough to recalibrate the threshold.