17/08/2025
Device: iPhone 11
Issue: No Power
Initial Findings:
Client reported that prior to the device losing power completely, a “Temperature Too High” warning would occasionally appear before automatic shutdown.
Diagnosis:
Upon diagnosis, the root cause of the no power issue was traced to the secondary power rail, specifically the VDD Boost circuit. Further inspection revealed a leaking capacitor within the VDD Boost line. After replacing the faulty capacitor, the device powered on successfully.
Subsequent Issue:
After restoring power, the “Temperature Too High” warning reappeared intermittently. This issue was traced to the South Speaker IC, which is known to be involved in temperature sensor readings and power distribution in that area.
Solution:
The South Speaker IC was replaced. After the replacement, the device was fully functional with no further temperature warnings.
Status: Repaired and tested. Device is now working properly.
