0x1400000 — SMC: silent sensor
SMC “BSC failure” panic: the system management controller (built into the SoC) periodically waits for a response from each mandatory sensor; this code was obtained in the lab when the electrical path between the microphone component on the USB flex, the filter and the logic board PMU is interrupted. With no response, it forces a restart, which repeats roughly every 3 minutes (≈180 s) as long as the sensor stays silent.
On iPhone 14 Pro Max, iPhone 14 Pro
USB module circuit: component (microphone) on the charging flex or logic board path to the PMU
High confidenceVerified sourceSMC: silent sensor
First check
First replace the charging port flex with a known-good part; if the panic persists, measure the connector and the filter on the logic board in diode mode (OL = damaged component) and bridge if the pads are intact.