Samsung Galaxy phones have two built-in ways to test hardware: the hidden *#0*# test menu and the diagnostics in the Samsung Members app. Here is how to use both, what each test checks, and how to test a Galaxy phone that has the menus blocked.
Samsung hidden test menu (*#0*#)
- Open the Phone app and go to the keypad.
- Dial *#0*#. A grid of test buttons opens straight away, with no call button needed.
- Tap Red, Green and Blue for dead pixels, Touch for dead zones, Receiver and Speaker for audio, Vibration, Sensor and the cameras.
- Press the Back button twice to leave a test.
On many US carrier models (Verizon, AT&T, T-Mobile) the code is blocked and nothing happens. Use Samsung Members or the free browser test below instead.
Samsung Members diagnostics
- Open Samsung Members (install it from the Galaxy Store or Play Store if it’s missing).
- Tap Support, then Phone diagnostics.
- Tap Test all, or pick single tests such as Battery status, Touch screen, Wi-Fi or Cameras.
Check battery health
- In Samsung Members › Phone diagnostics, run Battery status. Normal means healthy; Weak or Bad means the battery should be replaced.
- On newer One UI versions, also check Settings › Battery › Battery information for the charge cycle count and capacity.
Before a repair: Maintenance mode
Turn on Settings › Device care › Maintenance mode before handing a Galaxy phone to a repair shop. It hides your photos, messages and accounts while the technician tests the phone.
Test the parts built-in tools miss
Manufacturer diagnostics check that hardware is connected, but they rarely test everything you use. The MxMob phone diagnostic runs in the browser and checks every touch zone, left and right speakers, each camera lens, GPS accuracy, real Wi-Fi speed and more, then gives you a shareable report. Buying used? Follow the used phone checklist.
Diagnostic guides for other brands
Frequently asked questions
Why does *#0*# not work on my Samsung?
Carriers and some regions block the hidden test menu. Try Samsung Members › Support › Phone diagnostics instead, or open mxmob.com/check in Chrome or Samsung Internet to run a full test in the browser.
Is the Samsung *#0*# test safe?
Yes. It only runs hardware tests and doesn’t change settings or delete data. Leave each test with the Back button. Avoid other unknown codes, some of which open settings that can affect the phone.
How do I check a used Samsung phone before buying?
Dial *#06# and check the IMEI isn’t blacklisted, run *#0*# or the MxMob browser diagnostic, check battery status in Samsung Members, and make sure the seller has removed their Samsung and Google accounts.