H2 1. Two Root Causes of Full Screen Unresponsive Touch
H3 1.1 Physical Digitizer Damage
Cracked front glass breaks internal ITO touch circuits, leading to total touch failure; replacing a tested good digitizer will fully restore touch function.
H3 1.2 Mainboard Touch Circuit Fault
Damaged power supply capacitors cause abnormal touch voltage; new digitizers still fail after replacement, requiring motherboard component maintenance.


H2 2. Stepwise Professional Fault Diagnosis Process
- Swap a verified qualified digitizer for test; touch recovery = original touch panel damaged
- Touch still invalid after swap → power on device and measure touch LDO voltage with multimeter
- Abnormally low voltage = isolate faulty capacitors on mainboard for replacement
H2 3. Disassembly Protection & Bulk High-End Digitizer Criteria
- Do not overheat Face ID dot projector area during heating to avoid permanent facial recognition failure
- Wholesale Pro digitizer standards: anti-interference flex, high-strength tempered glass, 100% factory touch full inspection
- Support mixed batch bulk orders, independent dust-proof packaging for long-distance sea freight