About this replacement
Wiko View XL / M1790 — 3.85V Li-Polymer Replacement Battery (TLP17J21)
This 3.85V, 3000mAh Li-Polymer cell replaces the original TLP17J21 battery in the Wiko View XL and M1790 smartphones. It physically matches the original at 78 × 64 × 3.50mm and connects via the stock flex cable. Voltage and capacity figures are taken directly from the OEM specification.
- View XL and M1790 shared platform: Both models use the same battery bay dimensions, connector pinout, and BMS handshake protocol. One cell fits both without modification.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on a View XL unit. The BMS accepted the charge curve without error flags, and the protection circuit tripped correctly at the low-voltage cutoff threshold.
- First-cycle fast charge protocol: On first use after installation, disable fast charging and run one complete discharge-to-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated state.
Sudden shutdown at 20–30% on a replacement cell
A fresh Li-Polymer cell has a steeper voltage cliff than a worn cell the fuel gauge IC learned from. Under modem radio or screen load, the cell voltage drops briefly below the OS shutdown threshold even though the reported percentage looks safe. The gauge is still running the old cell's discharge curve. Run one full discharge down to auto-off, then charge uninterrupted to 100% — after that cycle, the coulomb counter resets to the new curve and the phantom shutdowns stop.
USB charging stops early or percentage reads incorrectly after swap
The fuel gauge IC on the View XL stores the previous cell's learned capacity in firmware. After a battery swap, this stored value is out of sync with the new cell, so the charge IC may terminate early or the displayed percentage may jump. Force a full recalibration: discharge the phone until it shuts off automatically, then charge to 100% in a single uninterrupted session with the screen off. Do not top-up or interrupt mid-charge. After one clean cycle, percentage reporting stabilises at ±3%.