About this replacement
Motorola MTP600 / MTP3000 Series — 3.85V Li-ion Replacement Battery (PMNN4522A)
This 3.85V, 3700mAh Li-ion battery replaces the PMNN4522A, QA02315AA, and QA02319AA packs fitted to Motorola MTP600, MTP3000, MTP3100, and MTP3150 radios. It slots into the same bay and connects through the same contact strip as the original. Capacity is 14.25Wh — matched to the original spec.
- MTP600 and MTP3000 platform fit: These models share the same battery bay geometry, contact pitch, and BMS handshake protocol. One pack covers the full MTP3x00 family because Motorola standardised the connector and voltage rail across the platform.
- Bench tested on actual hardware: We cycled this pack through PTT transmit loads on the MTP3100 and MTP3150. The BMS handled the current spike at key-up without tripping to protect mode, and the charger dock accepted the pack on first insertion after a contact wipe.
- First insertion into the charger dock: If the dock LED blinks fault on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The MTP platform runs a BMS handshake at insertion — a dirty or oxidised contact breaks that cycle before charging begins.
Why the MTP3000 cuts out mid-transmission on a new battery
A new cell ships at storage voltage — typically 3.6–3.7V, not a full 3.85V charge. On the MTP3000 series, the radio's low-voltage threshold can trigger a TX cutout if the pack voltage sags below about 3.4V per cell under sustained RF output. This is not a fault with the pack. Run one full charge cycle before heavy use and the BMS will calibrate the cutoff correctly against a fully charged baseline.
Bar indicator showing one fewer bar than expected after fitting this pack
The MTP platform reads battery level from voltage thresholds, not a chip-based fuel gauge. A new pack at storage voltage sits below the top threshold bracket, so the radio displays one or two bars even though the cell is not depleted. Charge the pack fully in the dock until the LED goes solid green, then reinsert the radio — the bar count will reflect the actual charged voltage, typically showing full at 3.85V.