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iPhone panic type
I2C bus stuck (SCL/SDA stuck low)
A device on that I2C bus holds the line low. The log names the bus and often the device.
Likely: A flex/device on the named bus (e.g. roswell = touch controller on 11 Pro Max i2c3)
Decoder match rule
i2c\d.{0,60}(?:SCL|SDA)\s*stuck|_checkBusStatusSteps
- Read the device name in the log.
- Disconnect the flexes on that bus one at a time; the one that clears the stuck line is the fault.
- Map bus -> connectors with the board schematic.
Known buses and devices
i2c0 on iPhone XS, iPhone XS Max (China), iPhone XS Max
On this bus: Charge-port (Lightning) flex assembly · Top sensor flex (Face ID / proximity) · Battery connector · Wide-angle camera
- Charge-port (Lightning) flex assembly confirmed
- Top sensor flex (Face ID / proximity) confirmed — Disconnecting it stopped the shutdowns (Face ID, True Tone and auto-brightness are lost while disconnected).
- Battery suggested
- A stuck line is shared by every device on the bus: disconnect one flex at a time and re-test (charge port first, then top sensor flex, then camera).
- Measure the i2c0 SCL/SDA lines in diode mode against a known-good XS board to find a short.
- iFixit Answers - iPhone XS Max i2c0 SCL stuck low (solved) (accessed 2026-09-29)
- iFixit Answers - iPhone XS Max i2c0 ad5860 (chosen solution: charge port) (accessed 2026-09-29)
- iFixit Answers - iPhone XS i2c0 ad5860 while charging (accessed 2026-09-29)
- iFixit Answers - iPhone XS Max i2c0 ad5860, battery suggested (unconfirmed) (accessed 2026-09-29)
Haptic (Taptic Engine) driver AD5860
- Charge-port (Lightning) flex assembly (the driver signals run through it on XS / XS Max) confirmed
- Replace / swap-test the charge-port flex first; also test with the Taptic Engine disconnected.
- iFixit Answers - iPhone XS Max i2c0 ad5860 (chosen solution: charge port) (accessed 2026-09-29)
- iFixit Answers - iPhone XS i2c0 ad5860 while charging (accessed 2026-09-29)
Display power-management IC (inside the display assembly)
- Display assembly (the PMU is part of the OLED panel) expert
- Test with a known-good display; the display PMU is not practical to replace on its own.
- iFixit Answers - iPhone X i2c3 SCL stuck low, device display-pmu (accessed 2026-09-29)
Touch controller (roswell)
- Display / touch assembly and its touch connector field
- Test with a known-good display; inspect the touch connector pins.
- iFixit Answers - iPhone 11 Pro Max i2c3 roswell (touch) SCL stuck low (accessed 2026-09-26)
lm3539 (iPhone 8 case: Taptic Engine; VCC: backlight driver)
- Taptic Engine confirmed
- Backlight driver / display suggested
- Swap-test a known-good Taptic Engine, then the display.
- iFixit Answers - iPhone 8 i2c3 lm3539 boot loop: Taptic Engine replaced, fixed (accessed 2026-10-02)
- VCC Board Repairs - iPhone panic log list (accessed 2026-09-26)
Ambient light sensor on i2c2 (iPhone 7)
- Front camera & sensor cable confirmed
- Replace the front camera & sensor cable with a known-good one.
- iFixit Answers - iPhone 7 i2c2 ALS panic: front camera & sensor cable replaced, fixed (accessed 2026-10-02)
Earpiece speaker amplifier on i2c2 (iPhone SE 2020)
- Front camera / earpiece flex suggested
- Top (earpiece) amplifier suggested
- Swap-test the front camera / earpiece flex.
Display EEPROM on i2c3 (iPhone 13 Pro)
- Display assembly suggested
- Test with a known-good genuine display.
- iFixit Answers - iPhone 13 Pro i2c3 display-eeprom: screen suggested (accessed 2026-10-02)
Sources
- iFixit - iPhone Kernel Panics (accessed 2026-09-26)
- iFixit Answers - iPhone 11 Pro Max i2c3 roswell (touch) SCL stuck low (accessed 2026-09-26)
- iFixit Answers - iPhone 7 Plus i2c3 SCL stuck low, mic-temp-sens1 (accessed 2026-09-26)
Hinglish me
I2C bus atka hua (SCL/SDA low par atka)
Us I2C bus ka koi device line ko low pakde hue hai. Log me bus ka naam aur aksar device ka naam bhi hota hai.
Log me device ka naam padho.
Us bus ke flex ek-ek karke nikaalo; jise nikaalne se line free ho jaaye wahi kharab hai.
Board schematic se bus -> connectors map karo.