About this replacement
Navman iCN 510 / iCN 520 / iCN 530 / iCN 550 — 3.7V Li-ion Replacement Battery (E3MT07135211)
This is a 3.7V 1500mAh Li-ion cell for the Navman iCN 510, iCN 520, iCN 530, and iCN 550 portable GPS navigators. It replaces OEM part E3MT07135211. Fit it when the original cell no longer holds enough charge to complete a navigation session.
- iCN 510 / 520 / 530 / 550 platform: All four models share the same battery bay dimensions, connector pin-out, and BMS handshake protocol — the same 3.7V cell works across the range without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the iCN platform. The BMS accepted the cell without fault codes, voltage settled at 4.18V at full charge, and low-battery cutoff triggered cleanly at the expected threshold.
- Cold-start behaviour after fitting: After installing this battery, power the unit on outdoors with a clear view of the sky and let it acquire a satellite fix before driving. A full power interruption resets the GPS receiver's almanac cache, so first fix after a swap takes 5–10 minutes — subsequent warm starts drop back under a minute once the cache rebuilds.
GPS accuracy reduced at low battery on the iCN series
When the iCN battery drops below roughly 3.5V, the unit reduces power to the GPS receiver module to extend remaining runtime. Lower receiver power means weaker satellite signal processing, which shows up as position drift or a reduced number of locked satellites. You may notice the map position jumping or route recalculations happening on straight roads. Keep the battery charged above the halfway mark during active navigation to avoid this.
iCN shuts off without warning before the battery indicator reaches empty
The on-screen battery gauge on the iCN series is calibrated to the original cell's discharge curve. A replacement cell with even slightly different internal resistance will cause the indicator to read inaccurately, so the unit hits the hardware voltage cutoff while the gauge still shows one or two bars remaining. This is not a fault with the new battery. After two or three full charge-to-cutoff cycles, the device re-reads the curve and the shutoff point aligns with the indicator. Cycle the battery fully at least twice before judging indicator accuracy.