Disclaimer: This guide is for educational purposes. Electronic repair requires skill. Incorrect soldering can permanently destroy the motherboard. When in doubt, consult a professional.
This report outlines the diagnostic and repair procedures for keypad failures in the Nokia 105 RM-908. Keypad issues in this model typically stem from one of three causes: physical damage (liquid/carbon wear), keypad filter IC failure, or PDSA/CPU disconnection. The "Keypad Ways" refer to the trace routes connecting the keypad membrane to the main logic board. nokia 105 rm 908 keypad ways
If a series resistor is found to be open-circuit (shows GR on one side but not the other), you can sometimes "short" or bridge the resistor to restore the path. Disclaimer: This guide is for educational purposes
If specific keys are not working, it is usually due to a break in the circuit path. You can trace and repair these using the following methods: Power Key Solution When in doubt, consult a professional
Since the keypad lines lead directly to the MediaTek CPU, a loose or damaged chip can cause entire rows or columns of buttons to fail. Troubleshooting the Keypad Ways