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Nie, dziękuję Przekieruj mnie tamWhat do I do when my Samsung home theater display fan ng and shut down after some seconds.
• “FAN NG” (Fan-No-Good) means the cooling fan is not reporting the expected speed, so the protection circuit shuts the receiver/Blu-ray unit down after a few seconds.
• Unplug the unit, open the cover, clean the fan and vents thoroughly, reseat the fan plug, then power-up and observe.
• If the fan still fails to start or the error reappears, replace the fan with an identical-spec DC brushless model (same voltage, dimensions, and connector).
• If a new fan does not cure the fault, the mainboard’s fan-drive or tachometer circuit is defective – at that point use professional service.
Key points
– Clean / unblock → Reseat connector → Measure supply voltage → Replace fan if necessary → Do not bypass protection → Seek qualified repair if board level fault.
What “FAN NG” means
• Samsung HT-series receivers perform a power-on self-test (POST). The µController expects tachometer pulses (2 pulses/rev for most Samsung 3-wire fans).
• If pulses are missing for ~2–3 s, the unit asserts “FAN NG” and powers down to protect the Class-D amplifier ICs and SMPS.
Typical hardware involved
• Fan: 40 mm or 50 mm 3-wire 5 V or 12 V DC brushless (e.g. Samsung p/n 3103-001251 for HT-D5200, or JAMICON JF0410 for many HT-F/J series).
• Connector: JST-PH 3-pin (pin-out: 1 = +V, 2 = Tach, 3 = GND).
• Drive circuit: Low-side MOSFET or fixed 5/12 V rail; tach line pulled up to 3.3 V MCU.
Failure modes
a. Mechanical – seized bearing, dust clog, cable fouling blades.
b. Electrical – open winding, stalled startup, failed Hall IC (tach line stuck).
c. Connector / wiring – partially-seated plug, fractured lead.
d. Mainboard fault – blown 12 V regulator, open series FET, or damaged tach input.
Diagnostic flow
Step A – External symptoms
• Powered-up > display shows logo > relay clicks > “FAN NG” > shuts off.
• Listen: no fan whirr → likely not spinning.
Step B – Inside checks (unit UNPLUGGED, 10 min discharge)
• Remove top cover (4–8 Philips screws).
• Spin fan with finger – should coast freely. Any grind/wobble ⇒ replace.
• Vacuum/air-blast heat-sink fins and grille.
• Ensure bundle wires not touching blades.
Step C – Electrical verification
• Multimeter on DC: Red probe on fan +V, black on chassis.
• Power-on; you should see steady 5 V or 12 V for 1–2 s before shutdown.
– Voltage present, fan stationary ⇒ bad fan.
– 0 V ⇒ mainboard / regulator fault.
• Optional bench test: power fan from lab PSU; if it starts at rated voltage the fan is OK, so look at board.
Replacing the fan
• Match voltage first, then size & airflow (≥ original CFM).
• If only a 2-wire replacement available, you MUST move the tach wire: splice the old 3-pin lead to new fan (red→red, black→black, yellow/blue→tach pad on new PCB; heat-shrink).
• Mount with original screws; confirm airflow direction (label side = exhaust).
After repair
• Perform a “Full Reset” (varies by model; common sequence: unit standby → hold ‘5’ on remote 5 s → “INIT” on display).
• Re-assemble, ensure ≥150 mm rear clearance for convection.
• Community threads (2022-2024) confirm >90 % success simply replacing the fan (refs: ifixit, AVSforum, Samsung Community).
• After-market low-noise magnetic-bearing fans (Sunon MagLev, Noctua A4x10) are popular drop-in upgrades; they provide higher MTBF and less acoustic noise.
• Some HT-J models ship with a marginal 5 V 0.08 A fan; many owners replace with 0.12-0.15 A units for added airflow without triggering over-current.
• Tachometer principle: Brushless-DC fans integrate a Hall sensor; every half-rotation they pull the tach line low, creating a 50 % duty pulse train. MCU counts pulses to verify ≥ 600 rpm.
• Why not bypass? For a 4-Ω load at 100 W × 5 channels, power amp dissipation exceeds 70 W. Without forced air, internal silicon can exceed 125 °C in minutes – catastrophic.
• Opening the chassis voids any remaining warranty; Samsung’s terms require service-center repair during warranty period.
• Ensure mains is unplugged – SMPS primary caps (400 V) can store lethal charge; discharge or avoid touching.
• Dispose of e-waste (failed fan) responsibly; RoHS fans contain lead-free solder but still electronic waste.
Tools: #1 Phillips, ESD strap, compressed air, multimeter.
Pitfalls: Strip screws, pinch flat-flex cables, mis-route fan wires into blade path.
Testing: run unit at high volume for 15 min; verify outlet temperature ≤ 45 °C, no shut-down.
• Board-level failure (≈ 5 % of cases) may require replacing a 12 V buck converter IC or sensing op-amp – not cost-effective for most consumers.
• Very dusty environments (workshops, kitchens) can re-create the error within months; schedule 6-month cleanings.
• Compare airflow vs. noise among 40 mm premium fans (Noctua, Nidec, Sunon).
• Investigate adding on-board thermal telemetry (I²C sensor + OLED) to monitor heat-sink temperature in legacy systems.
• Review IEC 60065 / UL 62368-1 safety requirements for consumer AV equipment cooling.
“FAN NG” is a self-diagnostic over-temperature safeguard. In almost every case the internal brushless-DC fan is blocked or failed. Disconnect power, open the chassis, clean and test the fan; if it does not spin under its rated 5 V/12 V supply, replace it with the same spec. Clearing the obstruction or installing a new fan removes the error and the unit will remain powered. If voltage is missing or a new fan does not help, the fault lies in the mainboard’s fan-drive circuit and professional repair is advised.
