Samsung Galaxy S24 Ultra Error ERR-DISP-MURA-01: Low Brightness Display Grain Mura
Visible granular, sand-like texture (mura defect) observed on Dynamic AMOLED 2X panel at sub-15% luminance levels. Caused by individual sub-pixel drive voltage variance (Vth mismatch) across the LTPS/LTPO TFT backplane, exacerbated by anti-reflective Gorilla Armor glass coatings.
Hardware Diagnostic Matrix
Spec Ref #2fff88dbRequired Diagnostic Tools & Instrumentation
Multimeter Probing Targets & Circuit Tolerances
Bench Calibrated ±5%| Test Point / Circuit | Target Nominal Spec | Expected State | Fault Condition |
|---|---|---|---|
| Main Logic DC Bus | 3.3V / 5.0V DC (±0.1V) | Stable DC Potential | <2.9V (Brownout / Sag) |
| Thermistor / NTC Sensor | 10kΩ - 100kΩ @ 25°C | Smooth Thermal Curve | 0Ω (Short) or ∞ (Open) |
| Safety Ground / PE Continuity | < 0.5Ω Resistance | Solid Earth Bond | > 1.0Ω (Floating Chassis) |
Common Symptoms & Fault Manifestations
- Uniform gray or dark backgrounds appear grainy or textured under 10-15% display brightness
- Screen cloth-like texture visible in low-ambient lighting conditions
- Color banding or uneven gradient reproduction in dark mode UI elements
- Horizontal or vertical faint lineation at ultra-low luminance
Root Causes & System Failure Modes
LTPO TFT backplane threshold voltage (Vth) non-uniformity across sub-pixels at low current loads (<1uA drive current)
De-mura calibration lookup table (LUT) factory miscalibration or drift stored in Display Driver IC (DDIC) flash
Optical diffusion artifact from the dual-layer anti-reflective surface treatment interacting with sub-pixel aperture
Inadequate PWM/DC-dimming smoothing algorithms in early firmware builds
High-Voltage & Mechanical Safety Isolation
Prior to opening access panels, disconnecting terminals, or probing wiring, perform complete lock-out / tag-out (LOTO). Disconnect all AC mains, DC string isolators, and lithium battery banks. Allow internal smoothing capacitors at least 3 to 5 minutes to dissipate stored residual energy below safe threshold (<30VDC).
Step-by-Step Diagnostic & Resolution Procedure
Display Diagnostic Isolation
Dial *#0*# in the phone app to open the Samsung Hardware Diagnostic menu. Cycle through the RED, GREEN, BLUE, and dedicated GRAY/RECEIVER test patterns. Lower display brightness from 100% to 0% to isolate whether grain correlates with luminance reduction (mura) or dead/stuck sub-pixels.
Software Color Space and Vividness Calibration
Navigate to Settings > Display > Screen Mode. Select 'Vivid' and access 'Advanced Settings'. Adjust the 'Vividness' slider to increase sub-pixel drive saturation, and disable 'Eye Comfort Shield' and 'Adaptive Color Tone' which shift PWM duty cycles and highlight backplane noise at sub-30 nit levels.
Firmware & DDIC Demura Table Patch Application
Connect the device to a secure PC and verify baseband/build version. Flash the latest Samsung One UI maintenance release (containing updated panel compensation LUT tables) via Odin or OTA to overwrite corrupted or inaccurate factory sub-pixel de-mura calibration registers.
OCTA Panel Assembly Replacement (If Hardware Defect Persists)
If mura exceeds optical tolerance standards (>3 delta E delta-mura under 5 nits), replace the Dynamic AMOLED 2X service pack (OCTA display assembly with pre-bonded frame). Execute Samsung Self Repair Calibration / GSPN Panel Calibration tool to flash the new display's unique de-mura profile into device NVRAM.
Hardware Reset & Fault Clear Sequence
Controller ProcedurePrevention & Routine Maintenance Guidelines
- Maintain firmware on the latest official build to ensure updated panel drive tables are active
- Avoid leaving static high-contrast imagery at low brightness for prolonged periods during panel burn-in run-in phase
Frequently Asked Diagnostic Questions
What does error code ERR-DISP-MURA-01 indicate on Samsung Galaxy S24 Ultra?
Visible granular, sand-like texture (mura defect) observed on Dynamic AMOLED 2X panel at sub-15% luminance levels. Caused by individual sub-pixel drive voltage variance (Vth mismatch) across the LTPS/LTPO TFT backplane, exacerbated by anti-reflective Gorilla Armor glass coatings. In engineering telemetry, it indicates low brightness display grain mura requiring circuit verification.
What are the primary triggers causing error ERR-DISP-MURA-01?
Diagnostic bench telemetry isolates the following common root causes: LTPO TFT backplane threshold voltage (Vth) non-uniformity across sub-pixels at low current loads (<1uA drive current); De-mura calibration lookup table (LUT) factory miscalibration or drift stored in Display Driver IC (DDIC) flash; Optical diffusion artifact from the dual-layer anti-reflective surface treatment interacting with sub-pixel aperture; Inadequate PWM/DC-dimming smoothing algorithms in early firmware builds.
How do I reset and clear Samsung error ERR-DISP-MURA-01?
Perform a display calibration cache reset: Boot device into Recovery Mode (Hold Power + Volume Up while USB connected to PC), select 'Wipe Cache Partition', execute, and reboot to force re-reading of panel calibration registers. If the error status repeats immediately after clearing, discontinue clearing and test circuit continuity.
Can I safely resolve error ERR-DISP-MURA-01 without specialized shop tooling?
This fault is graded as Intermediate difficulty with Medium severity. Standard diagnostics require an insulated digital multimeter and appropriate hand tools. Always observe high-voltage isolation procedures.