Unlike its predecessors (JDM-011 and JDM-030), the JDM-040 board moves several critical trace lines to improve production efficiency and physical durability. Key Architectural Shifts : The Go to product viewer dialog for this item.
Reflow or replace the main Mediatek MCU if data traces are intact. Test the USB D+ and D- lines for continuity to the MCU. jdm040 schematic exclusive
Blown input fuse (marked as 'F1' or 'F2' near the connector) due to using fast-charging phone bricks. 2. The 3.7V - 4.2V Battery Rail Unlike its predecessors (JDM-011 and JDM-030), the JDM-040
Check continuity across the input fuse near the battery/USB terminal wrapper. Test the USB D+ and D- lines for continuity to the MCU
Place one multimeter probe on System Ground and check the capacitors surrounding the main PMIC. If both sides of a capacitor beep in continuity mode, you have a shorted rail.