iPhone X — tp1a: Thermistor on the logic board
Low confidenceVerified sourceMissing sensor
On the iPhone X, tp1a means: Thermistor on the logic board (near the wide-angle camera connector) — uncertain attribution.
What does this code mean?
Watchdog panic: thermalmonitord no longer receives the reading from TP1A, probably a thermistor soldered onto the logic board; with no response for ~3 minutes, iOS restarts the iPhone. On iPhone X, one suggested lead is the thermistor at the top right of the wide-angle camera connector (the upper one).
Which part to test first?
Remove the silicone around the wide-angle camera connector and check the thermistor's resistor and capacitor; measure the NTC line (ground / open line).
The same code on other models
- iPhone 8Thermistor
- iPhone SE (1st generation)Rear camera thermistor on the logic board
Field cases
Did you repair one? Tell us what worked: it improves the database for everyone.