How to run
Open Phone app, dial *3001#12345#*, press Call
Phone Diagnostic Codes
iPhone Field Test Mode
Access iPhone field test mode for network diagnostics
Details
Opens iPhone's hidden field test mode showing detailed network information including signal strength in dBm, cell tower information, and network parameters. Useful for troubleshooting cellular connectivity issues.
Use caseNetwork diagnostics and signal strength testing
Works oniPhone (iOS)
CautionAdvanced mode; exit by pressing Home button
Utilities
Copy-paste helpers
Tip
Signal strength shown in dBm (lower is better; -50 to -120 dBm range)
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