iPhone 14 Pro / 14 Pro Max restarting every 3 minutes

If your iPhone 14 Pro or 14 Pro Max restarts about every 3 minutes, often with a short pink or purple flash, its power controller (SMC) has lost one of its sensors. The panic log names which one - here is what each code means on this model, and how sure repair technicians are about it.

Analyze your panic log How to find the log

What the panic log says

Open the newest panic-full file (Settings → Privacy & Security → Analytics & Improvements → Analytics Data). On a 14 Pro the important line looks like this:

SMC PANIC - ASSERT: target/d73/target.cpp:265: 0, SMC BSC failure ... S.sensor array 0 - 4 is 0x0, 0x80000, 0x0, 0x0, 0x0

The number that is not zero is the sensor code. Newer iOS versions print it in decimal instead: 524288 is the same code as 0x80000. d73 is the 14 Pro board, d74 the 14 Pro Max - both use the same codes.

Sensor codes on iPhone 14 Pro and 14 Pro Max

Code	Part	Confidence	Sources
`0x40000` 262144	Charging port flex	High	iFixit, iPad Rehab, iRepair Experts
`0x80000` 524288	Front sensor (proximity) flex, top of the screen	High - two repairs confirmed it	iFixit, iPad Rehab, iRepair Experts, iFixit case and NoPowerFix bench (below)
`0x100000` 1048576	Power button flex	High	iFixit, iPad Rehab
`0x41` 65	Battery data (battery or its connector)	High	iFixit, iPad Rehab
`0x20000` 131072	Logic board - bottom board (gyroscope) or the joint between the two boards	Medium - they agree it is the board, not on the exact part	iFixit, iPad Rehab
`0x10000` 65536	Listed as power button in two tables	Low - their own combined codes use 0x100000, so probably a typing slip	iPad Rehab, iRepair Experts

Two or three parts at once

Each sensor is one bit, so codes add up (in hexadecimal):

0xC0000 = charging port + front sensor flex
0x140000 = charging port + power button flex
0x1C0000 = charging port + power button + front sensor flex

Two parts at once usually means liquid damage or a repair that disturbed several cables. The analyzer splits combined codes for you.

Repairs that confirmed it

iFixit: an iPhone 14 Pro restarted every 3 minutes with S.sensor array 0 - 4 is 0x0, 0x80000, 0x0, 0x0, 0x0. The answer pointed to the proximity flex; the owner replaced the proximity sensor and later confirmed that everything worked once the sensor was changed.
NoPowerFix bench: our Hardware Specialist and bench technician fixed an iPhone 14 Pro Max with the same code (524288 = 0x80000) the same way - a new front sensor (proximity) flex stopped the restarts.

Test order

What was repaired last? A screen, battery, charging port or back-glass job is the first suspect - the part fitted, or a cable disturbed during it.
Inspect the flex and its connector under magnification: torn traces, liquid marks, a bent pin.
Test with a known-good original part plugged in. Unplugging the cable does not test it - an unplugged sensor is missing too, so the phone still restarts.
Expect side effects: a replacement front sensor flex loses True Tone and auto-brightness; a battery swap shows a non-genuine warning unless it is an Apple part paired with System Configuration.
If a good part does not stop it, the fault is on the logic board (often after liquid damage) - micro-soldering.
Do not restore iOS for this. An SMC panic happens below iOS; restoring only costs time and, without a backup, your data.

Not the same problem

A purple screen that stays, or purple lines without restarts, is usually the screen itself.
Restarts at random times without SMC PANIC in the log are a different panic - the analyzer reads those too.
The phone will not update or restore (error 4013, 9, 75...): see the restore error lookup.

Sources

Different code, or still restarting after the part swap? Post your panic log on the NoPowerFix repair forum - board-level technicians answer, and every new case improves the code tables.

Ask on the NoPowerFix forum