About this replacement
Trimble TSC2 / TDS Ranger 300 & 500 — 3.8V Li-ion Replacement Battery (39392848)
This 3.8V, 6600mAh Li-ion battery replaces the factory pack in the Trimble TSC2 and TSC2 Controller, as well as the TDS Ranger 300 and 500 Data Collectors. All four units share the same battery bay format, connector pinout, and BMS handshake protocol. Use the capacity figure from the product data above — 6600mAh / 25.08Wh — when logging equipment specs.
- TSC2 and Ranger 300/500 compatibility: These four models share a common battery housing, a matched three-pin connector, and an identical BMS communication line. The controller firmware reads cell voltage and temperature data over that line — so the pack must meet the same handshake spec across all four platforms, and this one does.
- Bench tested on actual hardware: We cycled this pack through the TSC2 power-on sequence and GPS acquisition load. The BMS held voltage within spec under the combined GNSS radio, display backlight, and Bluetooth draw without tripping a low-voltage cutoff or throwing a charge-error flag.
- First field deployment prep: After fitting the new pack, run a full charge before heading out, then let the TSC2 complete one full discharge cycle in the field. The device maps cell voltage thresholds during that first working cycle — skip it and the battery indicator will show erratic percentages for the first several sessions.
BMS lockout after the TSC2 sat unused in a carry case for months
Li-ion cells self-discharge slowly in storage. If the pack drops below approximately 2.5V per cell, the BMS trips a deep-discharge protection latch and blocks both charging and power-on. The TSC2 will show no response — no boot screen, no charge indicator — even with a known-good cable. To recover, apply a charger and leave it connected for at least 30–45 minutes without interruption; the BMS needs sustained trickle current to exit the protection state before normal charging resumes.
TSC2 shuts down mid-session during active GPS logging
Under sustained GNSS tracking load, the combined draw from the radio module, processor, and backlight can pull the cell voltage down faster than the indicator suggests. If an aging or partially discharged pack dips below the BMS low-voltage cutoff — typically around 3.0V under load — the unit shuts off instantly, even if the display showed 20–30% remaining moments before. This is a voltage-sag event, not a firmware fault. A fresh, fully charged 6600mAh pack provides enough headroom to prevent the voltage from collapsing under that sustained load.