In short
Many out-of-warranty series (B9, CX, C1, BX and related) can be saved by replacing the power supply board (power module) — instead of writing off the whole TV.
You need the correct EAY / board number, a tested replacement, and solid safety. Blind-buying used boards with the same aging damage is expensive roulette.
Find the EAY number — do not guess
LG OLED power supply boards typically carry an EAY… part number (and often an EAX PCB id). Without it, fit is unreliable — connectors, voltage variants and revisions differ.
How-to: read model label + board number — Find number, then search Parts.
Why the power module is the weak point
Opened LG OLED CX lying face down: the power supply board on the left, the green mainboard on the right, in the middle the black cover plate under which the T-Con board sits. The power supply board powers all boards.
On many LG OLED power supply boards, filter capacitors and related parts age. Symptoms: no start, or a start only after several attempts. Clicking without a picture and blink codes can come from the power supply board, but don't have to. If the TV switches off by itself after a while, the standby LED then stays red and every attempt to switch it on clicks without the TV starting, experience shows the mainboard is faulty. The LG CX series is particularly prone to this. We do not offer mainboard repairs. The power module is often the economical repair level — not the panel.
Background: won't turn on and Carli capacitors.
Safety — before opening
Measuring the large electrolytic capacitors of the installed power supply board in the LG OLED CX to confirm they are discharged. Here the multimeter still shows 30.6 V. Only continue once the voltage is below 30 V if possible.
Unplug the mains. Wait at least 2 hours, and discharge electrolytics on the power supply board before unplugging connectors or measuring. The large electrolytic capacitors can hold up to about 400 V even after switching off: measure with a range of at least 600 V and only continue once the voltage is ideally below 30 V. Mains and residual charge are lethal. Never work under power.
Unsure? Do not open — send it for Repair.
DIY swap vs manufacturer cost
The installed power supply board in the LG OLED CX: 3 connectors are attached, 2 to the T-Con board and 1 to the mainboard. It is held by 6 screws. These numbers apply to the LG OLED CX.
Manufacturer service after warranty is often expensive. A tested replacement power supply board or fixed-price board repair is cheaper for many B9/CX/C1/BX cases — if diagnosis points to the power supply board.
AmparioWeb tests boards before shipping and avoids untested used stock with the same film caps.
- Note and map EAY/EAX
- Unplug, wait at least 2 hours, discharge electrolytics and measure to confirm
- Photograph ribbon/power connectors
- Fit the new board, verify latches, then apply mains
- Do not “try boards” if fuse/short is suspected
What AmparioWeb offers
Correct power supply board identification, tested boards and fixed-price repair — including B9, CX, C1, BX.
Start: Find number, Parts or Repair.
Frequently asked questions
- Is the TV model number enough?
- Often not. Prefer the board EAY — see Find number.
- Can I fit any used power supply board?
- Risk: same aging capacitors. Prefer a tested AmparioWeb board.
- Do I need to solder?
- Full board swap is mostly screws/connectors — residual charge is still dangerous. Component-level repair on the power supply board is for specialists.
- Which series are typically OOW?
- Often requested: B9, CX, C1, BX — the wear pattern spans many OLED power supply board families.
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Power boards for LG OLED — tested under load, 12-month warranty.
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