# LG BU50NST will not turn on: repair or replace the power board

> Your LG BU50NST projector no longer responds? Its power board is identical in design to the one in LG OLED TVs. How to find the number and what AmparioWeb can do.

Your **LG BU50NST projector** will not turn on. No picture, no response to the remote. LG no longer sells it, and hardly any workshop takes it on.

We repair the power boards of the BU50NST in our workshop. They are identical in design to the power boards from LG OLED TVs. Replacements and a fixed-price repair are available.

## In short

The BU50NST is a laser projector. Its power board is identical in design to the power boards **EAY65689423** and **EAY65170411** from LG OLED TVs. We repair it in our workshop.

You have three options: have the board repaired, buy a tested replacement or sell us your defective board.

## What the BU50NST is

According to LG, the BU50NST is a projector from the ProBeam line:

- 4K UHD laser projector with 3,840 × 2,160 pixels.
- 5,000 lumens brightness.
- Light source rated for up to 20,000 hours.
- Marked as discontinued on LG's product page.

## The power board: identical in design to LG OLED

The power board of the BU50NST is identical in design to the power boards from LG OLED TVs. Two of them are in our shop: [EAY65689423](/en/bauteile/eay65689423-65-cx) and [EAY65170411](/en/bauteile/eay65170411-65-c9).

Check the number on your board before you order. It is printed in white on the board. If it matches one of the two numbers, the part fits. Help reading it is at [find your number](/en/nummer-finden). If your board shows a different number, write to us.

![Removed LG OLED power supply board EAY65689423 from above, component side, a multimeter to the right](https://amparioweb-products.fsn1.your-objectstorage.com/blog/lg-bu50nst-netzteil-reparatur-af023529.webp)

*This is what the power supply board EAY65689423 looks like, removed here and seen from the component side. Compare the number on your board before you order.*

## How to recognise a defective power board

If the projector does not respond at all, shows no indicator and makes no sound, that points to the power board. A check on the device confirms the fault.

More on troubleshooting power boards: [LG OLED will not turn on](/en/blog/lg-oled-fernseher-geht-nicht-mehr-an) and [mainboard or power board](/en/blog/lg-oled-mainboard-oder-netzteil). Those articles are about TVs; the power board is the same part.

## Safety notice

**Mains voltage is lethal.** Unplug the projector before you do anything. Do not open it and do not measure under power. Capacitors in the power board hold a charge after switching off. The device also contains a laser. If unsure, unplug it and ask us.

## Three ways with AmparioWeb

Whatever suits you best:

- Fixed-price repair: [request a repair](/en/reparatur).
- Buy a replacement: [see parts](/en/bauteile).
- Sell a defective board: [buyback](/en/ankauf).

## For companies, schools, practices and hotels

The BU50NST is often found in offices, training rooms, practices and hotels. You can use all three ways for business too. For purchases and repairs you receive an invoice by email.

## FAQ

**Is the LG BU50NST a TV?**

No. According to LG it is a 4K laser projector with 5,000 lumens from the ProBeam line. Its power board is identical in design to the one from LG OLED TVs.

**Which power board numbers fit the BU50NST?**

The numbers [EAY65689423](/en/bauteile/eay65689423-65-cx) and [EAY65170411](/en/bauteile/eay65170411-65-c9). Compare the number on your board before you order.

**Can I sell my defective power board?**

Yes, we buy defective boards. More under [buyback](/en/ankauf).

**Does LG still sell the BU50NST?**

LG's product page marks it as discontinued.

**What can AmparioWeb do for me?**

We repair at a fixed price ([repair](/en/reparatur)), supply tested [parts](/en/bauteile) or buy defective boards ([buyback](/en/ankauf)).