# LG OLED TV won't turn on > LG OLED won't power on? Aging 820 nF film capacitors in the PSU often cause it. Spot capacity loss — AmparioWeb repairs or supplies a tested replacement PSU. ## In short If your **LG OLED** TV **won't turn on**, starts unreliably, the **standby LED** stays dark, or you hear a soft **click** from inside, the cause is often not the panel — it is the **power supply** (**PSU**, Power Supply Unit / power board). Many LG OLED PSUs use **film capacitors** rated **820 nF** (**nanofarads**; equal to **0.82 µF** / microfarads). Over years they lose capacitance. Supply becomes unstable: boot failures, intermittent behaviour, aborted maintenance cycles. ## Typical failure pattern The pattern is often **intermittent**: sometimes the set starts, sometimes it is dead. After **unplugging** and plugging back in it may work briefly — then fail again. **Pixel refresh** (Pixel Refresher) aborts or never starts because the supply collapses during standby. Common observations in practice: - No response to remote or power button - Standby LED stays dark or flashes briefly - Short click / relay-like sound with no picture - Brief recovery after unplugging, then relapse - Pixel refresh or other standby jobs abort ## Root cause: aging film capacitors (often 824J 500V) Affected PSUs frequently carry yellow **film capacitors**, often from **Carli**. The marking **824J 500V** means: **824** = **820 nF** (0.82 µF), **J** = tolerance class, **500V** = rated voltage. These are filter and stability parts in the switch-mode supply — not cosmetic extras. **Aging** causes **capacitance loss**: measured values often sit in the **7xx nF** range, sometimes far lower — well under **100 nF**. With so little left, the supply becomes noisy. Result: unreliable start or collapse under load / in standby. ## Wide impact across the LG OLED line This wear pattern essentially hits the **power supplies of the LG OLED range** where these film capacitors were fitted — practically the whole OLED landscape that shares the same **PSU families**. Well-known series such as **C8 / C9 / CX / C1** and related chassis show up regularly in workshop practice. Not every single set is faulty. But the **component risk** runs through the OLED PSU landscape: wherever 820 nF film caps of this type sit, capacity loss over time is a realistic scenario — not a one-off mystery. ## Why film caps in the PSU matter so much Switch-mode supplies need stable filtering and clean voltage conditions so control rails, standby rails and the main supply can rise cleanly. When film caps lose capacitance, **PSU stability** drops: ripple rises, protection trips, soft-start fails. That is why the symptom often looks like “the TV is dead” — even when panel and mainboard may still be fine. Diagnosis starts at the **PSU**, not the expensive screen. ## Safety notice **Mains voltage is lethal.** Working on an open set and on the **PSU** means dangerous voltages. **Electrolytic capacitors** can hold high residual charge after unplugging — **discharge** before you measure or desolder. **Never measure under power** or swap parts while the TV is connected to the mains. If you are unsure: unplug, do not open, and leave diagnosis to a workshop. AmparioWeb offers tested **replacement PSUs** and **fixed-price repair** — see [Repair](/en/reparatur). ## Diagnostic pointers (high-level) Goal is rough triage — **not** a step-by-step guide to live work. After safe unplugging and wait / discharge of electrolytics, useful checks include: - Whether standby / auxiliary rails on the PSU appear at all (only by qualified methods, de-energised where required) - Visual check of fuses and burn / overvoltage marks - Electrolytics for bulging, leakage or discoloration - Suspect film caps (e.g. 824J 500V) desoldered and capacitance measured - Deviation of more than about **10 %** from nominal (820 nF) treated as critical — heavily aged caps often sit far below ## DIY repair vs professional replacement Replacing capacitors can be correct — with proper parts, clean soldering and PSU know-how. Used boards from the second-hand market are a gamble: they often still carry the **same aged Carli film caps**, and the fault returns. AmparioWeb’s stance is clear: prefer a **tested replacement PSU** or **fixed-price repair** over roulette with unknown old boards. Find parts and numbers via [Find parts](/en/nummer-finden) and [Replacement PSUs](/en/bauteile). ## What AmparioWeb offers You do not need a panel-replacement scare when the PSU is the cause. AmparioWeb helps identify the right **PSU**, supplies tested replacements, and repair paths for LG OLED no-power issues. Next step: check model / PSU number and request [Repair](/en/reparatur) — or search [Replacement PSUs](/en/bauteile). ## FAQ **Does this affect all LG OLED TVs?** At its core this wear pattern affects the **PSUs of the LG OLED range** that use these film capacitors — including known series such as C8/C9/CX/C1 and related PSU families. Not every single set is defective; the component risk still runs through the OLED PSU landscape. **Is replacing the 820 nF capacitors enough?** Often film-cap capacity loss is the main cause — then a proper swap can help. Extra damage (fuse, drivers, electrolytics) also happens. Measurement and a tested replacement PSU are often the safer path. **Panel or PSU — how do I tell?** No picture with clicking / missing standby LED / intermittent start after unplugging points strongly to the **PSU**. A panel fault more often shows image issues while power is up. Sorting that out is diagnosis — AmparioWeb helps map the fault. **What does 824J 500V on the capacitor mean?** **824** means **820 nF** (0.82 µF), **J** is the tolerance class, **500V** the rated voltage. These are typical film capacitors in many LG OLED PSUs. **Why does a short unplug sometimes help briefly?** After disconnecting, circuits discharge and soft-start / protection logic reset. With heavily aged caps, stability often lasts only briefly — then start problems return. That hints at supply issues, not “magic self-healing”. **Should I buy a used power board?** Be careful: used boards may carry the same aging film caps. Prefer a **tested replacement PSU** or fixed-price repair via AmparioWeb — see [Replacement PSUs](/en/bauteile) and [Repair](/en/reparatur).