iPhone 16 Pro Max (iPhone17,2) – Reboot every ~180 seconds – SMC BSC f

Hi everyone,

I'm trying to identify the component behind a recurring SMC panic on an iPhone 16 Pro Max (iPhone17,2).

• iPhone 16 Pro Max (iPhone17,2)
• Current iOS version installed
• Device had a liquid exposure / water damage incident approximately 3 months ago

• Phone boots normally
• All functions appear to work correctly
• Cellular, WiFi, Bluetooth, cameras, Face ID, charging, speakers and microphones appear functional
• No noticeable overheating
• No performance issues
• Device consistently reboots after approximately 2 minutes 50 seconds of uptime (~180 seconds)

I have collected multiple panic-full logs from different reboots.

All logs show the same panic:

SMC PANIC - ASSERT
SMC BSC failure, TAOC

Additional entries:

Misc(2) OUTBOX1 not ready

Sensor data:

S.sensor array 0 - 7 is:
0, 2097152, 0, 0, 0, 0, 0

F.sensor array 0 - 1 is:
0

The value is always:

2097152

which equals:

0x200000

• Opened device and visually inspected logic board and connectors
• No visible corrosion found
• No green residue
• No obvious liquid damage remains
• Cleaned accessible connectors with IPA (isopropyl alcohol)
• Reassembled device successfully
• Issue remains unchanged

Does anyone know what TAOC maps to on the iPhone 16 Pro Max / iPhone17,2?

Is TAOC:

• a temperature sensor?
• part of the USB-C / charging port assembly?
• a sensor on the lower daughterboard?
• a logic board sensor?
• another SMC-monitored peripheral?

Before moving to board-level repair I am considering replacing the complete lower USB-C / charging port assembly because of the previous liquid exposure.

Any information regarding TAOC, sensor array bit 0x200000, or similar cases would be greatly appreciated.

Thanks!