The key to unlocking repair and diagnostic functions lies in understanding the of that micro-USB port.
To enter (using Nokia’s proprietary tools like Phoenix Service Software or ATF Box), both D- and D+ need specific connections, usually via a USB-to-serial converter or a "USB to UART" adapter. Nokia 105 Rm 908 Usb Pinout
The Micro-USB port on the RM-908 follows the standard 5-pin configuration used for mobile charging and basic data functions. When the phone is viewed with the port facing you (and the wider side of the trapezoid at the bottom), the pins are ordered : Pin Number Description Pin 1 VCC / VBUS +5V Power Supply for charging. Pin 2 Data - (D-) Negative data line (often used for software flashing). Pin 3 Data + (D+) Positive data line. Pin 4 ID Typically not connected (NC) on this model. Pin 5 GND Ground / Negative terminal. Common Repair Scenarios The key to unlocking repair and diagnostic functions