Repair OS for Android & iPhone board-level technicians
Start with the symptom. Follow guided measurements. Get the repair path — every step backed by bench evidence, never a guessed value.
01 · Symptom first
Pick the symptom. AIFlasher lays out the measurement order, the fault domains to test and the exact guides for Android and iPhone.
Measurement order for no power-on, no charge response, no display. Each step must pass before the next one is meaningful.
Liquid indicators, corrosion, previous rework, battery connector and missing components.
Supply at the battery connector. Record standby current, response to the power key and the curve shape.
VBAT and VPH_PWR / PP_VDD_MAIN voltage, then resistance or diode-to-ground against a known-good board.
Always-on rails, power-key / PON line, 32.768 kHz clock and reset release.
USB enumeration (9008, BROM, Preloader, DFU, Recovery) shows how far the SoC progressed.
Inject only after rail identity and its operating voltage are known. Re-measure after the repair.
Listed in measurement order, not by probability.
Android
iPhone
Academy
Measurement order for not detected, not charging, slow or intermittent. Each step must pass before the next one is meaningful.
Known-good charger and cable. Inspect the port for lint, corrosion and bent pins.
A USB meter is valid here: confirm VBUS and whether the phone detects the charger.
Separate "not detected" from "detected, no charge" — they are different fault domains.
Battery voltage, thermistor (NTC) and the battery data / fuel-gauge line.
VBUS → OVP → charger IC → VSYS / VBAT handoff, measured point by point.
Timed charge with current and temperature recorded.
Listed in measurement order, not by probability.
Android
iPhone
Academy
Measurement order for logo loop, restarts after boot, timed restarts. Each step must pass before the next one is meaningful.
Logo loop, restart after reaching the system, or a timed restart (for example around 3 minutes on iPhone).
iPhone panic-full log, or Android boot reason and last kernel log, before touching hardware.
Rebound pattern versus early stall separates late-boot faults from power-sequence faults.
When a log names a sensor or bus, isolate that flex or peripheral first.
AVB / vbmeta, slot state, restore or flash result.
Stable boot across repeated cycles with every original peripheral reconnected.
Listed in measurement order, not by probability.
Android
iPhone
Academy
Measurement order for no signal, imei blank, baseband unknown, sos. Each step must pass before the next one is meaningful.
Known-good active SIM, known coverage, airplane mode and network mode settings.
Is the IMEI and baseband / modem firmware version present, blank or unknown?
Logs, ServiceMode / engineering screens and modem firmware state.
Antenna contacts, coax, front-end module / PA, transceiver — band by band.
Modem PMIC rails and reference clock against the exact board reference.
Registration, calls and data on more than one band.
Listed in measurement order, not by probability.
Android
iPhone
Measurement order for black screen, no backlight, lines, touch faults. Each step must pass before the next one is meaningful.
Vibration, sound, USB enumeration or current progression before blaming the display path.
A known-good panel separates the screen from the board in one step.
Damaged pins, torn or pinched flex, corrosion on the board connector.
Panel supplies, backlight boost / LED driver and enable lines.
Touch controller supply, I²C / SPI activity and interrupt line.
Full-screen image, full brightness range and all-area touch.
Listed in measurement order, not by probability.
Android
iPhone
Academy
Measurement order for black viewfinder, focus, flash or ois faults. Each step must pass before the next one is meaningful.
Swap a known-good module to separate the camera from the board.
Inspect the board connector and flex for damage or corrosion.
Analog, digital and I/O supplies, enable and reset lines.
I²C control bus and MIPI CSI data lanes.
Autofocus, OIS and flash circuits when only one function fails.
Every lens, focus, flash and video recording.
Listed in measurement order, not by probability.
Android
Android guide not yet published — use the steps on the left with the exact board reference.
iPhone
Measurement order for no sound, mic dead, earpiece or loudspeaker faults. Each step must pass before the next one is meaningful.
Earpiece, loudspeaker, which microphone, or headset — they are different circuits.
Known-good speaker or mic, and a clean mesh.
Call, voice recorder, speakerphone and video — note which fail.
Codec / amplifier supplies and I²C / I²S activity.
On iPhone, check whether a panic log names an audio bus or sensor.
Every path in every mode.
Listed in measurement order, not by probability.
Android
Android guide not yet published — use the steps on the left with the exact board reference.
iPhone
Measurement order for wet, corroded, dropped in water. Each step must pass before the next one is meaningful.
Do not power the phone to "test" it while liquid may be present.
Corrosion under shields, on connectors and around the PMIC and charging area.
Isopropyl alcohol or ultrasonic cleaning within the board’s tolerance, then dry fully.
Main-rail and key-rail resistance / diode-to-ground against a known-good board.
DC PSU with a conservative current limit; watch the current shape.
Route to the workflow for whatever fault remains after cleaning.
Listed in measurement order, not by probability.
Measurement order for storage not found, 9008/dfu, isp and ic identity. Each step must pass before the next one is meaningful.
Read the top marking and decode capacity, eMMC / UFS and generation in the IC database.
EDL, BROM, DFU or restore behaviour and how it changes with storage isolated.
VCC / VCCQ (eMMC, UFS) or NAND rails on iPhone.
CMD / CLK / DAT (eMMC), M-PHY & reference clock (UFS), PCIe (iPhone NAND).
Identity read, health report and partition table.
Full write / read and a firmware boot.
Listed in measurement order, not by probability.
Measurement order for itunes errors, flash failures, avb, frp after flash. Each step must pass before the next one is meaningful.
Restore error code or the flash tool log line — not a paraphrase.
Exact model, region and build against the official firmware metadata.
Where in the restore or flash sequence does it stop?
Storage rails and interface; baseband for late restore errors.
Slot state, vbmeta and dynamic partitions on Android.
Clean boot and integrity check after flashing.
Listed in measurement order, not by probability.
02 · Guided measurement
Enter each reading as you take it. AIFlasher interprets it and tells you which measurement to take next. A reading narrows the fault domain; it does not identify a component on its own.
Rules: AIFlasher Android No Power analyzer · generic DC-PSU zones, not board-specific limits. Exact-model known-good data always overrides them.
Pick the DC current behaviour you see. iPhone diagnosis uses the shape of the curve, not a single number.
Signatures: AIFlasher iPhone No Power reference set · reference-derived, confirm on the exact board.
03 · Workspace
Each tool hands its evidence to the next — from the first reading to the verified repair report.
Device → symptom → observation → ranked next test → confirmation. Saves the case in your browser and exports a report.
Start a case IPHONEPaste, upload or photograph a panic-full log. Decodes the panic string and the SMC sensor array for 117 reference entries.
Analyze a log STORAGEDecode top markings to capacity, eMMC or UFS and generation. 387 indexed IC records with evidence tiers.
Decode a marking CASESOne case from first observation to checked outcome. Export and import backups; print the repair report.
Open workspace ANDROIDBoot reason, kernel panic and flash-tool errors decoded into the next check.
Decode a log FIRMWAREStock ROMs and flash files by brand and model, with the boot / AVB checks to run before you flash.
Find firmware04 · Repair cases
Every case records the symptom, the measurement that changed and the proof after repair. A fix that "worked" is not enough on its own — the grade shows how strongly the cause was confirmed.
Redmi Note 10 Pro (Sweet)
Samsung Galaxy S21 Ultra (Exynos)
Samsung Galaxy A52s 5G
Poco X3 Pro (Vayu)
OnePlus 9 Pro (Lemonadep)
05 · Board repair
Brand-specific depth once you know the fault domain: rails, boot stages, signal names and service-mode paths.
Samsung · Xiaomi / Redmi / Poco · Oppo / Realme · Vivo · OnePlus · Motorola — Qualcomm, MediaTek, Exynos and Unisoc paths.
Boot sequence, current signatures, panic and restore intelligence, sandwich-board isolation and baseband.
06 · Evidence standard
AIFlasher does not stop at "replace this IC". Every path records why the next test follows, and a value without a source stays marked unknown.
Exact failure, reproduced
Where to measure
Known-good reference, with source
Your actual bench reading
Which fault domain it supports
The measurement that confirms it
07 · Knowledge base
Free courses for technicians, students and institutes — bench safety, DC current diagnosis, UFS/eMMC ISP, panic logs and an 8-week lab curriculum.
