Falk FA Z10 GPS Navigator Replacement Battery SR454362 3.7V

Falk FA Z10 / NEO 620 Series — 3.7V Li-Polymer Replacement Battery (SR454362)

This 3.7V, 1400mAh Li-Polymer cell replaces part number SR454362 in the Falk FA Z10 and NEO 620 series portable GPS navigators. It fits the FA Z10, NEO 620, NEO 620 LMU, and NEO 640. Voltage and capacity match OEM spec exactly.

• FA Z10 and NEO 620 platform fit: These models share the same battery bay dimensions, connector pinout, and 3.7V supply rail. One cell covers the full group without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the GPS platform. The protection circuit tripped correctly at the low-voltage cutoff threshold and accepted charge without error from a standard dock.
• Cold-start satellite acquisition after fitting: After a full power interruption, the FA Z10 performs a cold start and must rebuild its satellite almanac from scratch. Power the unit on outdoors and leave it stationary — first fix after a swap typically takes 5–10 minutes. Subsequent locks are faster once the almanac is cached.

GPS accuracy reduced at low battery on the FA Z10

When the SR454362 cell drops below roughly 3.5V under load, the FA Z10 reduces receiver sensitivity to conserve power. This shows up as wider position scatter or missed turn prompts — not a software fault. Charging the unit before a journey keeps the cell above the threshold where the receiver runs at full sensitivity. A fresh cell at 3.7V holds the receiver in full-power mode throughout normal use.

FA Z10 shuts off without warning before the low-battery indicator appears

The battery indicator in the FA Z10 reads state of charge from a voltage estimate calibrated to the original cell's discharge curve. A new cell — or a degraded one — can sit at a voltage the device reads as 30–40% remaining, then drop sharply under the GPS receiver and display load and hit the hardware cutoff. This looks like a sudden shutdown with no warning. The fix is to run two or three full charge cycles so the device re-calibrates its estimate against the actual cell. After conditioning, low-battery warnings should reappear at the correct charge level.