About this replacement
Magellan RoadMate 5045 Series — 3.7V Li-ion Replacement Battery (03A250XEQ0301)
This 3.7V 720mAh Li-ion cell replaces OEM part 03A250XEQ0301 in the Magellan RoadMate 5045, 5045-LM, and 5045LM portable GPS navigators. It restores battery-powered navigation when the original cell no longer holds a charge. Dimensions are 50.00 x 35.00 x 6.00mm — verify against your existing cell before fitting.
- RoadMate 5045, 5045-LM, and 5045LM fit: All three variants share the same PCB layout, connector pinout, and battery bay dimensions. The BMS on this cell communicates with the charge controller on all three boards without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a RoadMate 5045 unit. The BMS engaged correctly at low-voltage cutoff, and the charge circuit accepted the cell without fault codes or cutoff interruptions.
- Cold-start satellite acquisition after swap: After fitting this cell, power the unit on outdoors and let it acquire a full satellite fix before driving. A cold start after complete power removal takes 5–10 minutes for first fix. Subsequent warm starts drop back under a minute once almanac data is cached.
GPS accuracy reduced at low battery on the RoadMate 5045
The RoadMate 5045 scales back receiver sensitivity as voltage drops toward the cutoff threshold. This happens before the unit shuts off — the GPS antenna draws less power, but position accuracy degrades noticeably. You may see the position dot drifting or snapping between streets on low charge. Keeping the cell above 3.5V prevents the receiver from entering this reduced-power state.
RoadMate 5045 shuts off without a low-battery warning
The battery indicator on the RoadMate 5045 reads from a fuel gauge calibrated to the original cell's discharge curve. After a swap, that calibration is off — the indicator can show two bars while the cell is already near cutoff voltage. The BMS then trips at 3.0V and the unit cuts power with no visual warning. Run two full charge and discharge cycles after fitting the new cell to let the fuel gauge recalibrate to the new cell's curve.