iPhone 13 Pro Max — sensor array 0x4000: Battery
Medium confidenceVerified sourceSMC: silent sensor
On the iPhone 13 Pro Max, 0x4000 means: Battery (data lines / fuel gauge).
What does this code mean?
SMC “BSC failure” panic: the system management controller (built into the SoC) periodically waits for a response from each mandatory sensor; here, the data link with the battery is lost. With no response, it forces a restart, which repeats roughly every 3 minutes (≈180 s) as long as the sensor stays silent.
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
- iPhone 13 ProBattery
- iPhone 13 miniBattery
- iPhone 13Battery
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