About this replacement
Magellan RoadMate 1400 Series — 3.7V Li-Polymer Replacement Battery (5390-B101-0780)
This 3.7V, 1300mAh Li-Polymer cell replaces the original battery in the Magellan RoadMate 1400, 1412, 1430, and 1445 portable GPS navigators. It restores power to the touchscreen display and GPS receiver when the original cell has degraded or failed. Capacity is 4.81Wh at a physical size of 60.22 × 36.14 × 4.91mm.
- RoadMate 1400 series compatibility: The 1400, 1412, 1430, and 1445 all share the same battery bay dimensions, connector pinout, and 3.7V supply rail. One cell covers the full group.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the RoadMate platform. The BMS held charge termination correctly and the device booted without triggering low-voltage lockout.
- First-fix after swap: After fitting this cell, power the unit on outdoors before driving. A cold start after full power removal takes 5–10 minutes to acquire a satellite fix. Subsequent warm starts drop to under a minute. Skipping this step outdoors before first use can make the unit appear unresponsive to satellite signals.
RoadMate shutting off without warning at apparent mid-charge levels
When an aged battery is swapped out, the device's voltage-to-charge indicator is still calibrated to the old cell's discharge curve. The new cell holds a flatter voltage curve through most of its capacity, then drops sharply near the end. The RoadMate interprets that final voltage drop as an immediate cutoff rather than a low-battery warning, so the screen goes dark without showing the usual alert. Running the unit through two or three full discharge-and-charge cycles recalibrates the indicator — charge to 4.2V and discharge until automatic shutdown each cycle.
GPS accuracy dropping noticeably during long navigation sessions
Some RoadMate units reduce GPS receiver sensitivity when battery voltage sags below approximately 3.5V under load. At reduced sensitivity, the unit may drop from six or more satellites down to three or four, which is enough to degrade positioning accuracy on tight urban routes. This is a firmware-level power-saving behaviour, not a hardware fault. Keeping the unit plugged into the vehicle charger during extended trips bypasses the threshold entirely and keeps the receiver at full sensitivity.