About this replacement
VDO Dayton PN4000 Series — 3.7V Li-ion Replacement Battery (52340A 1S2PMX)
This 3.7V 2100mAh Li-ion cell replaces the original battery in the VDO Dayton PN4000, PN4000-TSN, and BAT-4060 portable GPS navigators. It matches the OEM voltage rail and physical footprint at 56.00 × 35.60 × 12.00mm. Fit this cell and the unit powers on without firmware prompts or connector rework.
- PN4000 and PN4000-TSN compatibility: Both units share the same battery bay geometry, connector pinout, and 3.7V operating rail. The BAT-4060 designation is the OEM battery reference for this platform — all three part numbers draw from the same cell specification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the PN4000 platform. The BMS accepted charge from the OEM dock without flagging an error, and the protection circuit tripped correctly at the low-voltage cutoff threshold before the unit could enter a deep-discharge state.
- Cold-start satellite acquisition after swap: After fitting this cell, power the GPS on outdoors before driving. Full power removal clears the warm-start cache, so the receiver performs a cold start — expect the first satellite fix to take 5–10 minutes. Subsequent power cycles lock significantly faster once the almanac is rebuilt.
GPS battery draining faster during active turn-by-turn navigation
Active navigation runs the GPS receiver, processor, and display backlight simultaneously — a combined load that draws considerably more current than standby. The PN4000 display brightness setting has the largest single impact on drain rate. Dropping brightness one or two steps below maximum measurably reduces the load on the cell. If the unit will sit in a windscreen mount with a power cable available, running it wired eliminates battery draw entirely during longer journeys.
PN4000 shuts off without warning before the low-battery indicator appears
The fuel gauge in the PN4000 reads a voltage estimate, not a direct capacity measurement. After a full battery swap, that estimate is uncalibrated — the unit's shutdown threshold can trigger before the on-screen indicator reaches one bar. Run two full charge and discharge cycles through the OEM dock to let the firmware recalibrate the voltage-to-capacity curve. After calibration, the low-battery warning appears at the correct threshold, typically around 3.5V per cell.