Samsung Galaxy S24 Ultra Error DISP-MURA-PWM60: Display Grain and Mura Defect
Sub-pixel luminance non-uniformity across the Dynamic AMOLED 2X panel caused by low-drive current mismatch and fine metal mask (FMM) variance at low brightness thresholds, exacerbated when the display controller throttles refresh rates to 60Hz or lower during 492Hz PWM cycles.
Hardware Diagnostic Matrix
Spec Ref #1c9588afRequired 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
- Noticeable sandy, gritty texture across dark gray and solid color backgrounds under 15% brightness
- Horizontal banding and luminance unevenness visible at 60Hz adaptive refresh rate step-down
- Color shifting and crushed shadow detail in low-light environments with Eye Comfort Shield active
Root Causes & System Failure Modes
Sub-pixel individual TFT drive threshold voltage (Vth) deviation exceeding compensation limits under low current (<50 nA per sub-pixel)
Display Driver IC (DDIC) de-mura calibration look-up table (LUT) offset mismatch during low-frequency variable refresh (VRR) states
Anti-reflective Corning Gorilla Armor coating interaction with underlying sub-pixel diffusion layer altering perceived focal plane
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
Software LUT Calibration & Vividness Adjustment
Navigate to Settings > Display > Advanced Settings. Increase the 'Vividness' slider to the middle or maximum setting to force sub-pixel compensation re-indexing. Ensure firmware is updated to build S928BXXU1AXCA or later containing DDIC look-up table patches.
Refresh Rate and PWM Stabilization
Install ADB and run 'adb shell settings put system peak_refresh_rate 120' and 'adb shell settings put system min_refresh_rate 120' to lock dynamic panel refresh to 120Hz, preventing the low-frequency 60Hz PWM shift that magnifies Vth discrepancy.
Service Mode Factory De-Mura Calibration
Boot device into engineering mode using code *#0*#. Select 'RECEIVER (WHITE)' and cycle through individual R, G, B channels. Access 'Sub-Pixel Mura Tuning' menu to initiate internal DDIC OTP (One-Time Programmable) de-mura compensation refresh sequence.
OCTA Panel Assembly Replacement
If panel luminance deviation exceeds 8% delta-E across adjacent pixel clusters in hardware diagnostics, power down device, safely disconnect the battery, disconnect display FPC from mainboard, and replace the factory Dynamic AMOLED 2X display assembly using genuine service pack GH82-33455A.
Hardware Reset & Fault Clear Sequence
Controller ProcedurePrevention & Routine Maintenance Guidelines
- Avoid running continuous static high-contrast UI elements at minimal brightness levels for extended periods
- Keep device firmware updated to ensure latest display driver LUT calibrations are applied
Frequently Asked Diagnostic Questions
What does error code DISP-MURA-PWM60 indicate on Samsung Galaxy S24 Ultra?
Sub-pixel luminance non-uniformity across the Dynamic AMOLED 2X panel caused by low-drive current mismatch and fine metal mask (FMM) variance at low brightness thresholds, exacerbated when the display controller throttles refresh rates to 60Hz or lower during 492Hz PWM cycles. In engineering telemetry, it indicates display grain and mura defect requiring circuit verification.
What are the primary triggers causing error DISP-MURA-PWM60?
Diagnostic bench telemetry isolates the following common root causes: Sub-pixel individual TFT drive threshold voltage (Vth) deviation exceeding compensation limits under low current (<50 nA per sub-pixel); Display Driver IC (DDIC) de-mura calibration look-up table (LUT) offset mismatch during low-frequency variable refresh (VRR) states; Anti-reflective Corning Gorilla Armor coating interaction with underlying sub-pixel diffusion layer altering perceived focal plane.
How do I reset and clear Samsung error DISP-MURA-PWM60?
Perform a soft DDIC reset by dialing *#2663# and tapping 'TSP FW update (General)'. Once completed, force restart the device by holding Volume Down and Power buttons simultaneously for 10 seconds. If the error status repeats immediately after clearing, discontinue clearing and test circuit continuity.
Can I safely resolve error DISP-MURA-PWM60 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.