Locate a working point on the same line (often a test point on the back of the board or a series resistor).
In rare instances, excessive drops cause the MediaTek processor to lose connection with the keypad traces. Phase 1: Preliminary Cleaning and Software Reset
Route the wire cleanly around the edge of the display frame.
To identify the physical and electronic paths (referred to as "ways") of the keypad matrix on the Nokia 105 RM-908, and to provide diagnostic and repair solutions for common keypad-related failures.
You're looking for a helpful paper or guide on the Nokia 105 (RM-908) keypad ways. Here are a few resources that might assist you:
The Nokia 105 (RM-908) keypad layout works on a matrix system where keys are grouped into specific rows and columns
If the specifically fails to boot the device but the battery rails check out perfectly:
When specific columns, rows, or individual buttons fail to respond, the issue is almost always a broken trace (track) connecting the keypad matrix to the processor. This comprehensive article serves as an expert mobile repair blueprint for tracing, troubleshooting, and running to restore functionality to a faulty Nokia 105 RM-908 keypad. 1. Understanding the Nokia 105 Keypad Matrix Architecture
The Nokia 105 RM-908 often uses small passive components (resistor arrays or EMI filters) near the keypad connector.