iTunes / iOS Restore Error Code Diagnosis Tool

Type an error code to instantly see its meaning, the general checklist, and L2 board-level causes (CPU / SDRAM / NAND / baseband). Below: a full error-code table, 2026 repair-rate estimates, and FAQ.

Don't spam retry on a restore error (it may enter DFU). Nine out of ten errors are solved by a fixed order: original MFi cable + rear USB 2.0 port (avoid hubs) → repair drivers → disable firewall/AV → exit recovery and re-restore → change PC → repair. Among them 4013/4014 are mostly hardware communication, 53 the Face/Touch ID module, 3194/3004 downgrade signing issues.
iTunes restore error code diagnosis tool illustration
iTunes / iOS restore error code diagnosis (general checklist + L2 board-level causes)

Step 1: the general checklist (nine out of ten errors start here)

Whatever the code, run this order first — many people struggle for hours when a new original cable and the right USB port would have fixed it. See also the full error-code guide and the restore guide.

General restore-error troubleshooting order Swap original MFi cable to rear USB2.0, repair drivers, disable AV, exit recovery and re-restore, change PC, then repair. Restore error · general order 1) Original MFi cable + rear USB 2.0 port Avoid USB hubs / front panel / adapters 2) Update system / helper / iTunes + repair drivers Toolbox to iTunes & driver repair (Apple driver issues are common) 3) Disable firewall / antivirus / security suite 4) Exit recovery / force into DFU and re-restore Don't yank the cable or spam retry; prefer keep-data restore 5) Try another PC (rule out OS compatibility) 6) Still failing -> mostly hardware (storage / baseband / module) -> repair Especially 4013/4014 stuck at a fixed %, error -1 baseband
Fig 1: general restore-error order (from cable to repair, step by step)

Step 2: L2 board-level causes (by stall position -> part)

When software checks fail and it stalls at a fixed percentage, the code maps to a specific board part. The table below is a repair-level mapping (compiled from public repair material, not first-hand testing, for direction only).

Error code -> logic board part (when stuck at a fixed %) 4005CPU and CPU circuit 4014Temp SDRAM / NAND not detected 9 (late report)storage not read / cold solder / power 1baseband CPU not detected -1baseband power missing / short 3baseband & code chip circuit 3004 / 3014 / 2005 (reported very early)cable / PC / network (not hardware) 3194firmware unsigned -> pick a signed one
Fig 2: error code to board part, repair-level mapping (public repair material, not first-hand)
iPhone logic board error code repair area illustration
Tried everything in software and still failing? Mostly hardware — locate the board part by error code.

Full error-code table (meaning · general fix L1 · L2 board-level cause)

CodeCommon meaningGeneral fix (L1)L2 board-level cause
9Storage not read / powerChange PC, check storage power, retry a few timesReported only after a long wait: storage not read, cold solder, missing power, or CPU comms fault
11System drive low on spaceFree up the C: drive and retrySoftware, not hardware
14Insufficient power / USB anomalyOriginal cable, rear USB port, retryMostly cable / port / power contact; rarely storage power
4005Hardware communication breakOriginal MFi cable + rear USB2.0, disable firewall, repair drivers, change PCCPU and CPU circuit
4013Hardware comms break (most common)Same; if stuck at fixed %, look at hardware~60% storage, after 80% baseband/power; RAM-CPU-storage path
4014Hardware communication breakSame as 4013Temp SDRAM & circuit; or NAND not detected, pad lift / power short
53Touch ID / Face ID module or flexRestore via phone hotspot; module damage needs repairFace/Touch ID module or its flex (hardware)
3004Server refused / verification closedConfirm still signed, check hosts/proxy, latest clientNetwork / signing service, not hardware
3194Apple stopped signing (downgrade)Can't restore that old version; pick a signed oneSigning policy, not hardware
26Verification just closedRefresh signing status and recheckSigning policy, not hardware
1Baseband CPU not detectedMostly hardware; after checks, seek repairCheck baseband power rails and baseband CPU cold solder
3Baseband relatedMostly hardware; repairBaseband, code chip and its circuit
-1Baseband communication failureMostly hardware; after checks, seek repairMissing baseband power rail / short to ground / poor CPU soldering
-50Server communication timeoutCheck network/proxy, latest client, retry off-peakNetwork layer, not hardware

iTunes restore error / repair data (2026 estimate)

2026 estimate compiled from public repair-industry and data-recovery material (not vendor-official numbers, not first-hand testing).

4013/9/4014 software vs hardwareSoftware-fixable ~20-30% > hardware (NAND/CPU etc.) ~70-80%
4014 main causeMostly NAND not detected: pad lift / PP3V0_NAND power short (chip itself often fine)
Stall position -> part~60% -> storage · after 80% -> baseband / power
Board / data-recovery costBoard repair $40-120, chip-off / data recovery $120-220 (estimate)
Board-repair success rate (est.)about 65-75% (depends on part and model)
iTunes restore error causes (soft vs hard) and board-repair success rate 2026 estimate
Fig 5: soft- vs hardware-cause split and board-repair success rate (2026 estimate, not vendor figures)
iTunes restore error board-level cause split and where stalls map to parts
Fig 6: board-level cause split — which board part a stall at each percent points to (2026 estimate)

Real-world quick judgments

Restore errorcheck WHEN it reports Right at start (3004 / 3194 / -50)Network / signing / proxy — not hardware. Change network, pick a signed version Only after stalling (4013 / 4014 / 4005)Mostly hardware — ~60% storage, after 80% baseband/power; repair by part Only after a long wait (9 / 14)Mostly storage not read / power — don't keep soft-restoring, test storage
Fig 7: classify by WHEN it reports — at start = network/signing, on stall = hardware, after long wait = storage
Enter Recovery / DFU correctly, then re-restore (don't yank the cable) 1) Cable to PCoriginal cable + rear USB2.0open the assistant 2) Model key comboVol+ → Vol− → hold Sideuntil black = DFU / Recovery 3) Re-restoreprefer keep-data restoreelse run the checklist
Fig 8: enter Recovery / DFU correctly then re-restore (don't yank the cable or spam retry)
Two rules: 1) turn off Find My iPhone before restoring (else Activation Lock), and prefer keep-data restore; 2) on an error, don't yank the cable or spam retry — use Exit Recovery Mode to boot normally first. For downgrade signing see the restore guide.
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FAQ

How do I diagnose restore error 4013/4014?

Hardware communication break. Original MFi cable + rear USB2.0 (avoid hubs), disable firewall/AV, repair drivers, change PC; ~60% storage, after 80% baseband, repeated failures need repair.

Where do 4005 / 4014 / 9 map on the board?

4005 the CPU and circuit; 4014 SDRAM or NAND not detected; error 9 (late) storage not read / cold solder / power. Hardware, needs repair.

Can error 53 be fixed?

Usually the Face/Touch ID module or flex. Restore via hotspot first; module damage needs hardware repair.

What do 3194 / 3004 mean?

Downgrade-related: 3194 = Apple stopped signing, can't restore; 3004 = server refused / verification closed. Pick a signed version.

What are errors 1 / -1?

1 = baseband CPU not detected; -1 = baseband communication failure (power / short / cold solder). Mostly hardware; seek repair after checks.

What about 11 / 14?

11 = low system-drive space, clean and retry; 14 = power / USB anomaly, use an original cable and rear USB port.

What if it fails halfway?

Don't yank the cable or spam retry. Exit Recovery to boot first, then run the general checklist and re-restore.

Why "restorable" but still fails?

Restorable only means signed; success also depends on cable / USB / driver / hardware and OS compatibility. Work the checklist item by item.

How do I enter DFU / Recovery to re-restore?

Connect an original cable, open the assistant; press the model key combo (Vol Up tap → Vol Down tap → hold Side until black) to enter DFU / Recovery, then keep-data restore. Don't yank the cable or spam retry.

Software-fixable vs hardware fault?

Reported at the very start (3004/3194/-50) = network / signing, fixable; only after stalling at a fixed % (4013/4014) = hardware; error 9 after a long wait = storage. Stalls that survive cable/PC swaps are basically hardware.

For restore basics and SHSH / downgrade signing see the restore guide; the illustrated error-code reference is at error-code guide; back up first, see backup guide and data recovery. Download the official app from the download page.

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