About this replacement
Astro C40 TR Wireless Controller — 3.7V Li-Polymer Replacement Battery (U603048PVG)
This 3.7V, 1000mAh Li-Polymer cell replaces the original battery in the Astro C40 TR Wireless Controller. It restores wireless operation on PlayStation 4 and compatible devices when the factory cell no longer holds a usable charge. Dimensions are 48.20 x 32.20 x 6.40mm — match these against the original before installing.
- C40 TR platform fit: The C40 TR uses a dedicated Li-Polymer cell tied to the controller's charge IC and fuel gauge IC. Voltage, physical size, and connector orientation all have to match — swapping an incorrect cell can confuse the BMS and cause false charge readings or premature cutoff.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the C40 TR platform. The BMS accepted the cell without error flags, and the charge IC brought it to full capacity without tripping protective cutoffs.
- Fuel gauge calibration on first use: After installing, run one complete wireless play session to full automatic cutoff before recharging. The C40 TR's fuel gauge IC sets its empty reference point against the first full discharge cycle — skipping this step causes the battery indicator to read inaccurately from the start.
Why the C40 TR fuel gauge jumps or reads incorrectly after a cell swap
The C40 TR uses a coulomb-counting fuel gauge IC that tracks charge relative to a stored discharge curve. When a new cell goes in, that stored curve no longer matches the actual cell characteristics. The IC has no reference point for the new cell's capacity floor, so it interpolates — which shows up as the percentage jumping or stalling at fixed points. Run three to five full discharge-and-charge cycles and the IC will remap its curve to the replacement cell. After that, readings stabilise.
Controller disconnects mid-session before the battery indicator shows low
This happens when combined wireless radio and rumble motor draw pulls the cell voltage below the BMS cutoff threshold before the fuel gauge has updated the display. The fuel gauge updates at intervals — it can show 20% while the actual cell voltage has already sagged to the cutoff point under load. A new cell needs three to five conditioning cycles to reach rated capacity and hold voltage under that combined draw. If disconnects persist after cycling, check that the battery connector is fully seated — a loose connection raises internal resistance and worsens voltage sag under load.