Introduction
Android includes a set of built-in dial commands, often called Android secret codes, that give access to diagnostic tools and system information not shown in everyday settings. These MMI (Man-Machine Interface) and Android dial codes are used by manufacturers, networks and engineers, but they can also be useful for everyday users. With the correct codes, you can check signal strength, review hardware performance, confirm device details such as IMEI, and identify issues that may be affecting battery life, connectivity or call quality. Used carefully, they offer a simple way to understand and improve how your phone is working, without installing third-party apps.
When and how to use the secret codes?
Device ID and Software
Unknown device identity, theft check, MDM enrolment failure
- Dial: *#06#
- Usage: Displays the unique IMEI number
- Benchmark: IMEI must match box, invoice, and network records
Update failures, compatibility problems
- Dial: ##1234##
- Usage: Confirms installed firmware version
- Benchmark: Must match latest approved vendor build for that model
Unsupported or outdated software
- Dial: ##44336##
- Usage: Shows build date and version
- Benchmark: Build date within vendor support window (typically <24 months)
Poor performance, app crashes
- Dial: ##3264##
- Usage: Confirms installed RAM
- Benchmark: Must match manufacturer specification (e.g. 8 GB = ~7-7.5 GB usable)
Network, Signal and Data
Poor signal, slow data, dropped calls
- Dial: ##4636##
- Usage: View signal strength, network type, data state
- Benchmark: LTE: -80 to -95 dBm = good | 5G: -70 to -90 dBm = good | RSRP worse than -110 dBm = poor
Coverage or handover problems
- Dial: ##7262626##
- Usage: Detailed radio and band diagnostics
- Benchmark: Stable connection with minimal band switching in a static location
Wi-Fi is not connecting or is unstable
- Dial: ##232339##
- Usage: Tests Wi-Fi radio functionality
- Benchmark: Signal stronger than -65 dBm for reliable use
Slow speeds or frequent dropouts
- Dial: ##232340##
- Usage: Checks Wi-Fi performance and errors
- Benchmark: Packet loss <1%, stable throughput
Network access blocked
- Dial: ##232338##
- Usage: Identify device on managed networks
- Benchmark: MAC visible and consistent (unless randomisation enabled)
Pairing or tracking issues
- Dial: ##232337##
- Usage: Verify Bluetooth identity
- Benchmark: Stable MAC, no random resets
Hardware Tests
Dead pixels, colour distortion
- Dial: ##0##*
- Usage: Full RGB and brightness test
- Benchmark: No dead pixels, uniform brightness
Unresponsive or inaccurate touch
- Dial: ##2664##
- Usage: Tests touch accuracy across the screen
- Benchmark: 100% touch area response, no dead zones
Touch lag or erratic behaviour
- Dial: ##2663##
- Usage: Confirms touch controller firmware
- Benchmark: Firmware matches current OS build
Weak vibration or screen dimming
- Dial: ##0842##
- Usage: Tests haptics and backlight
- Benchmark: Consistent vibration, even backlight
Distortion or low volume
- Dial: ##0289##
- Usage: Tests loudspeaker output
- Benchmark: Clear sound, no crackling at max volume
Media playback issues
- Dial: ##0673##
- Usage: Tests audio codecs
- Benchmark: All tones play cleanly
GPS and Location
Slow or inaccurate location
- Dial: ##1472365##
- Usage: Tests satellite lock
- Benchmark: Fix within 10-30 seconds outdoors
Navigation drift or dropouts
- Dial: ##1575##
- Usage: Satellite strength diagnostics
- Benchmark: ≥6 satellites locked with SNR >20
Camera and Services
Camera crashes or poor image quality
- Dial: ##34971539##
- Usage: Verify camera firmware
- Benchmark: Firmware aligned with OS version
Sync, push notifications failing
- Dial: ##8255##
- Usage: Monitor Google service activity
- Benchmark: No persistent sync errors
Samsung-Only (UK)
Unknown hardware faults
- Dial: #0#
- Usage: End-to-end component testing
- Benchmark: All tests pass with no errors
Rapid battery drain
- Dial: *#0228#
- Usage: Check voltage and health
- Benchmark: Voltage: ~3.7 – 4.4 V | Health: “Good”
PC or Android Auto is not recognised
- Dial: *#0808#
- Usage: Change USB mode
- Benchmark: Device recognised instantly by the host
Reset (High-Risk)
Persistent software bugs
- Dial: ##7780## – Factory Reset (Apps Only)
- Usage: Reset settings and apps
- Benchmark: Issue resolved post-reset
Redeployment or resale
- Dial: 27673855# – Full Factory Wipe
- Usage: Complete data erase
- Benchmark: Device boots to initial setup screen
UK Practical Note
- Carrier restrictions apply (EE/O2/Vodafone/Three)
- Android 13+ limits legacy access
- Best diagnostic depth: Samsung, Pixel, Xiaomi
Conclusion
Secret dial / MMI codes are a useful way to get a better sense of what is going on with your Android phone. If you use them carefully, they can help you spot problems, check how things are running, and decide what to do next, whether that means changing a setting or looking into a repair. Not every code will work on every device, but knowing what’s available can save you time and help you avoid unnecessary steps.