The Power IC (also called PMIC, Tristar, or U4000) manages charging and power rails (3.3V/5V) for the A15/A16 CPU.
Failure due to poor cables/adapters, overheating, impact, moisture, or charging during use.
Symptoms include no charge, no power-on, shutdowns, and fast battery drain.
Repair involves hot-air desoldering of faulty IC and micro-soldering a new one per SOP, followed by power and voltage validation.
Requires microscope, BGA hot-air station, and board-level testing equipment; only specialized shops can perform.
Estimated cost: $60–150 depending on damage extent and technician skill.
Post repair checks: charging function, current draw, stable boot, cellular/Wi-Fi, Face ID, and thermal behavior.