A reasonably cheap fix for a Samsung LN-S2338W LCD TV

Last year I got a Samsung LN-S2338W 23″ LCD TV at an insanely low price. The catch was that it didn’t behave very well–the buttons didn’t always work, and the TV liked to turn itself off randomly, or sometimes it even turned itself on.

It wasn’t haunted–it needed a power supply. Samsung TVs of this era had a recall due to defective capacitors in their power supplies, but either this one never got fixed, or wasn’t fixed completely. But it’s not too difficult to fix it yourself.

To open it up, I had to remove 10 screws from the back. Two of the screws are in the middle, near where all the ports are. Once I had the TV open, I could see three circuit boards. The power supply is the middle board, held in place with four screws. I could see one of the capacitors was visibly bulging. The tops of the capacitors should always be flat, like Kansas.

I probably could replace that bad capacitor, and it would make sense to replace all of the reasonable-sized caps on the board while doing it, but I haven’t done a component-level repair since I was a teenager. I found two numbers on the board, BN96-02585A and MGM23-N, and searched Ebay for them. Sure enough, I found a match. Several people were selling salvaged boards that came out of TVs with busted screens at prices high enough to make it worth their while but low enough to make my TV worth fixing.

Swapping these boards is a safe procedure as long as you’re very careful. There are five cables to unplug from the old board and four screws to remove. Snap a photo or otherwise make note of the cable connections because there are six connectors on the board but only five cables. One connector is unused. Don’t touch anything but those connectors and the screws. There are warning stickers on the heat sinks. Trust me, they can bite you. So can the nasty light bulb-sized capacitors that are marked 300V DC. Yes, those caps hold a charge of 300 volts in them.

If I haven’t scared you off yet, here’s the safe way to remove the board: Remove the four screws, keeping one hand behind your back while doing so–if one hand is behind your back, it’s very difficult for you to complete a circuit and get a shock that can harm you–and then lift the board out from one corner. If you have to use two hands, only touch the corners. Set the board aside on a book or something similarly flat, portable, and nonconductive. The old board will discharge itself over the course of a few weeks.

Carefully place the new board where the old board was, replace the four screws, and replace the five cables. Replace the TV back, replace enough of the screws to hold it together–the two in the middle and the four corners ought to be enough–and try it out. If everything works fine, replace the remaining screws. If it doesn’t, disassemble the TV again and double-check all your cable connections.

The process took me no more than half an hour.

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