The "Invalid PPI" error on Samsung phones is scary sounding, but it is almost always a that requires no hardware expertise. In 90% of cases, wiping the cache partition (Fix #2) or resetting NFC services (Fix #3) solves the issue instantly.
adb logcat -b all | grep -i "invalid ppi\|density\|xdpi\|ydpi" invalid ppi samsung
Before attempting technical fixes, try to break the error loop with a hard reset: The "Invalid PPI" error on Samsung phones is
If the phone restarts to the same error, move to the firmware repair below. Step 2: Flash Official Firmware via Odin Step 2: Flash Official Firmware via Odin Some
Some third-party launchers or "mods" (like older versions of Xposed modules or Magisk modules) attempt to dynamically change resolution and density on the fly. If the module crashes or applies a value that One UI rejects, the system will panic and display the error.