About this replacement
Magellan Maestro 4700 — 3.7V Li-ion Replacement Battery (0392607k2)
This 3.7V, 1100mAh Li-ion cell replaces the original battery in the Magellan Maestro 4700 and MA4700SGXUC portable GPS navigator. It matches the OEM dimensions at 50.40 × 36.60 × 5.57mm and slots into the existing battery bay without modification. Capacity figures come from the product data — 1100mAh / 4.07Wh.
- Maestro 4700 and MA4700SGXUC fitment: Both model variants run the same 3.7V battery bay with identical connector pinout and BMS communication line — one cell covers both units without adapters or wiring changes.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Maestro 4700 platform and confirmed the BMS accepted the cell without throwing a fault, held the correct cutoff voltage, and reported charge status accurately on-screen.
- Cold-start after power interruption: After fitting this cell, power the GPS on outdoors before driving. The unit performs a cold satellite acquisition after any full power removal — first fix can take 5–10 minutes. Subsequent warm starts drop that to under a minute once the almanac is cached.
GPS accuracy reduced at low battery on the Maestro 4700
As the cell voltage drops toward its lower threshold, the Maestro 4700 scales back receiver sensitivity to protect remaining capacity. This shows up as position drift or slower route recalculation — not a map or signal issue. A degraded original battery that only holds partial charge will trigger this behaviour frequently. Fitting a fresh cell at full 3.7V nominal keeps the receiver running at full sensitivity throughout a journey.
Maestro 4700 shutting off without low-battery warning
A worn cell loses voltage sharply in its final 10–15% of capacity — the on-screen indicator still shows one bar, then the unit cuts off. The battery indicator is calibrated against a healthy cell's discharge curve; an aged battery collapses faster than the firmware expects. This replacement cell restores the correct discharge curve so the indicator has time to cycle through all warning stages. After fitting, allow a full charge before use so the firmware re-establishes its voltage-to-percentage mapping.