ERA WIZA16 HTC Touch Diamond Replacement Battery 3.7V 2350mAh

ERA MDA Vario — 3.7V Li-ion Replacement Battery (WIZA16)

This is a 3.7V, 2350mAh Li-ion replacement battery for the HTC Touch Diamond, sold under the MDA Vario branding. It slots into the original battery compartment and connects via the same three-pin contact pad. OEM part number WIZA16 matches the original cell specification.

• MDA Vario platform fit: The Touch Diamond and MDA Vario share the same chassis and battery bay. Both use the WIZA16 form factor with an identical connector pinout and BMS handshake protocol — no hardware modification needed.
• Bench tested on actual hardware: We ran this cell through a full charge and load cycle on the Touch Diamond platform. The BMS accepted the charge handshake immediately, voltage held steady under display and wireless load, and the protection circuit tripped correctly at low-voltage threshold.
• Fuel gauge recalibration on first cycle: After fitting this battery, disable any fast charge mode and run one complete discharge-to-charge cycle before normal use. The fuel gauge IC on the Touch Diamond calibrates its coulomb counter against the new cell's discharge curve — skipping this step leaves the percentage readout unreliable for the first several cycles.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff failure, not a capacity problem. The Touch Diamond's processor and modem draw a combined current spike during active calls or screen-on polling that the fuel gauge IC cannot predict from a freshly installed, uncalibrated cell. When instantaneous voltage drops below the BMS cutoff threshold — typically around 3.0V under load — the phone shuts off even though the reported percentage still looks healthy. One full discharge-charge cycle lets the coulomb counter map the actual voltage-to-capacity curve of the new cell. After calibration, the shutdown threshold aligns with real remaining capacity and the cliff behaviour stops.

Phone not powering on after the battery sat in storage

Li-ion cells self-discharge during storage, and if voltage drops below approximately 2.5V per cell the BMS enters a lockout state to prevent damage. The Touch Diamond will show no response — no boot screen, no charge indicator. Connect the phone to a low-current USB charger and leave it untouched for 20–30 minutes. The charge IC trickle-charges the cell back above the BMS re-enable threshold, typically 2.9V, at which point the protection circuit resets and normal charging resumes.