iPhone X — tg0b: Battery
On the iPhone X, tg0b means: Battery / battery connector / battery data lines (Q3200–Q3201, I2C0 SMC→gauge).
What does this code mean?
Watchdog panic: thermalmonitord no longer receives data from the TG0B battery sensor; with no response for ~3 minutes, iOS restarts the iPhone. On iPhone X, Repair Wiki classifies TG0B and TG0V as “battery related”: dead battery, damaged connector or broken data lines.
Which part to test first?
Check whether the battery percentage is displayed (stuck at 0–1% or “Service” = the iPhone can no longer read the battery), inspect the battery connector pins and the small components around it under the microscope (often torn off during disassembly), test with a known-good battery, then measure the battery data lines at the connector in diode mode (OL = open line).
The same code on other models
- iPhone SE (2nd generation)Battery
- iPhone 12 Pro MaxBattery
- iPhone 12 ProBattery
- iPhone 12 miniBattery
- iPhone 12Battery
- iPhone 11Battery
- iPhone XS MaxBattery
- iPhone XSBattery
- iPhone XRBattery
- iPhone 11 Pro MaxBattery or charging port flex
- iPhone 11 ProBattery or charging port flex
- iPhone 7 PlusBattery
- iPhone 7Battery
- iPhone 8 PlusBattery
- iPhone 8Battery
- iPhone SE (1st generation)Battery data line: resistor near the battery connector
Field cases
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