iPhone 12 Pro Max — tg0b: Battery

High confidenceVerified sourceMissing sensor

On the iPhone 12 Pro Max, tg0b means: Battery (battery sensors / data line).

What does this code mean?

Watchdog panic: thermalmonitord no longer receives readings from the TG0B sensor, linked to the battery (temperature / fuel gauge data); with no news from it for ~3 minutes, iOS restarts the iPhone, in a loop as long as the sensor stays missing.

Which part to test first?

Check whether the battery percentage is displayed (a reading stuck at 0–1% reveals lost battery data), inspect the battery connector (bent pins), test with a known-good battery, then measure the connector's data lines in diode mode.

The same code on other models

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