Required Skill Levels:
Advanced Module / PCB Level
Identify faulty section in PCB
Replace ICs, MOSFETs, charging IC
Perform BGA rework (if required)
Circuit tracing using schematics
Expert / Micro Component Level
Diagnose at component level
Read and understand schematic diag
Use DSO, multimeter, and power sup
Fault tracing
Replace SMD components (0402 / 02
Reball BGA IC
Identify and resolve short circuit root
Perform circuit modification if design
Limitations exist
Handle micro soldering under micros