Samsung TV & Audio HW-Q990C 11.1.4 Channel 546 Watt Soundbar with Dolby Atmos, DTS:X, and Wireless Subwoofer POWER CYCLE Error Fix: Soundbar Repeatedly Turns Off and On

Error code POWER CYCLE on the Samsung TV & Audio HW-Q990C 11.1.4 Channel 546 Watt Soundbar with Dolby Atmos, DTS:X, and Wireless Subwoofer means: Soundbar Repeatedly Turns Off and On. Soundbar turns off and immediately back on in a loop, or turns off after a few seconds of operation. Causes: (1) overheating — ensure ventilation, don't place in enclosed cabinets, (2) power supply instability — failing capacitors cause voltage sag under load, triggering protection shutdown and restart, (3) firmware crash during boot — corrupted firmware update, (4) CEC power conflict — multiple CEC devices wrestling for control. Immediate fix: unplug 2 minutes, press power button while unplugged 15 seconds (drain capacitors), plug directly into wall outlet (not surge protector). If cycling persists after factory reset, power supply or main board hardware failure.

The most successful fix is "Replace Soundbar Power Supply Board" (hard difficulty, ~90 minutes). Estimated DIY cost: $15-$30. HomeMD has 2 community-ranked fixes for this error.

This error is rated high severity. You should address it promptly — continued use could cause damage or safety concerns.

Yes — the top-ranked community fix ("Replace Soundbar Power Supply Board") is rated hard difficulty and takes about 90 minutes. Tools needed: T10 Torx screwdriver, Plastic spudger, Multimeter.

DIY cost: $15-$30. Professional repair typically costs $150-$250. Many homeowners save money by trying the top-ranked community fix first.

The Samsung TV & Audio HW-Q990C 11.1.4 Channel 546 Watt Soundbar with Dolby Atmos, DTS:X, and Wireless Subwoofer has 8 other known error codes, including: ARC (HDMI ARC Input Mode — Connection Issues), ARC NO AUDIO (No Sound via HDMI ARC/eARC Connection), ATMOS PASSTHROUGH (Dolby Atmos Not Being Received from TV), AUDIO DROPOUT (Audio Drops Out Intermittently), AUTO STANDBY (Soundbar Auto Powers Off After 15-20 Minutes), and 3 more.

Error code POWER CYCLE also appears on 7 other Samsung TV & Audio models: HW-B650 3.0 Channel 330 Watt Soundbar with DTS Virtual:X and Bluetooth, HW-S800B Ultra Slim 3.0 Channel 360 Watt Soundbar with Dolby Atmos and Bluetooth, QN55LS03BAFXZA 55" Class The Frame QLED 4K Smart TV, QN65Q80CAFXZA 65" Class Q80C QLED 4K Smart TV, QN65QN90CAFXZA 65" Class QN90C Neo QLED 4K Smart TV, QN65S90CAFXZA 65" Class S90C OLED 4K Smart TV, and 1 more. The fix may vary by model, so check each model's specific page for tailored repair steps.