About this replacement
Garmin 010-00543-00 Series — 7.4V Li-ion Replacement Battery (010-10517-00)
This is a 7.4V, 2200mAh Li-ion battery for Garmin GPS navigators in the 010-00543-00 family, including EGM478 and related models. It replaces OEM part numbers 010-10517-00, 010-10517-01, 011-00955-00, and 011-00955-02. Fit the cell, power on the unit, and the device picks up where the original battery left off.
- 010-00543-00 family compatibility: These models share the same 7.4V two-cell architecture, identical connector pinout, and the same BMS handshake protocol — which is why one cell covers the full variant range including 100054300 and 3580100054300 derivatives.
- Bench tested on actual hardware: We cycled this cell through full charge-discharge on a 010-00543-00 unit. The BMS accepted the cell immediately, reported correct voltage to the fuel gauge, and held a stable charge curve throughout the discharge cycle with no unexpected cutoffs.
- Cold-start satellite acquisition after fitting: After any full power interruption — including a battery swap — the GPS performs a cold start. Take the device outdoors and power it on before your first use. First satellite fix takes 5–10 minutes; subsequent warm starts resolve in under a minute once the almanac is rebuilt.
GPS battery draining faster during active navigation than standby
Active navigation draws on two power-hungry systems simultaneously: the GPS receiver chip scanning and tracking satellites, and the backlit display running at full brightness. In standby or track-logging mode with the screen off, current draw drops significantly. If drain feels unusually fast in navigation mode, reduce display brightness — it is the single largest controllable load on the 2200mAh cell. The GPS receiver itself consumes a fixed draw that cannot be reduced without disabling satellite functions.
Device shuts off without warning before the battery indicator hits empty
The on-screen battery indicator is calibrated against the original cell's discharge curve. A new cell with a slightly different voltage slope can hit the device's low-voltage cutoff threshold before the indicator registers as empty. This is a fuel gauge calibration lag, not a fault with the cell. Run two or three full charge-discharge cycles through active navigation use — the device's charge algorithm will re-map the cutoff point against the new cell's actual curve and the warning will realign to the correct charge level.