Samsung un46c8000 broken board

[whywontyouwork]

Hey,

I am new to this depth of tinkering with electronics, so I was wondering if anyone had similar problems before I dive head first.

I have a Samsung un46c8000xfxza with some problems. The HDMI ports do not work. When I connect my computer, my computer knows that something is connected and I can even move my mouse over to the TV. But the TV says that there is no signal. I have tried this with other computers. Sometimes I can get a signal across but if the signal is refreshed, it loses it.

When I connect it to the TV cable, it picks up channels. But if I leave it on a channel for about 30 seconds, the TV is stuck at the channel. It may say the channel has changed, but it shows the same thing on every channel. I need to turn the TV off for a while to reset the channel. It comes up fuzzy if I turn the TV on too soon.

I have upgraded the firmware and this did nothing. I also called Samsung support and they say I need a new board. I am not looking to spend $300 on the board when I can get a new TV for that. I looked at Samsung forums, and other people had the same problem. They were under warranty so they said Samsung replaced their board. The board model number is BN9402696F or BN9402696A, both work. I took the TV apart but did not see any lose connections.

I am going to take a more closer look at the board and test the components. I was wondering if anyone had similar problems or had any insight.

Thanks!

[CapLeaker]

Re: Samsung un46c8000 broken board

If you are new to this depth of electronics and don't have the proper smd rework tools, I think you should either find yourself a replacement board somehow or the same TV with a smashed screen etc., or get a different TV.

[whywontyouwork]

Re: Samsung un46c8000 broken board

That's an odd reply for a repair forum.

I am getting into fixing electronics and this is my first project.

[sordids999]

Re: Samsung un46c8000 broken board

Posting pictures of the back of your tv showing the boards with clear pictures may help you more with fixing your problem

[mmartell]

Re: Samsung un46c8000 broken board

Capleaker means to say that troubleshooting main boards is exceedingly difficult due to their complexity and the fact no schematics will be available to you. There are things you can check like voltage regulators and bad solder connections by applying heat (hair dryer) or cold (air cannister upside down) to see if symptoms change. Many times the bga connections beneath the main ic crack and cause varying symptoms.

It is common even on this board for people to replace main boards where possible and for others to be stuck with tv's like yours because they cannot find reasonable replacements.

[whywontyouwork]

Re: Samsung un46c8000 broken board

Thank you for the explanation mmartell. Yeah I looked into replacement board but could not find any cheap enough. Also tried to sell it with no avail. I will post pictures of the board though. It does not look like anything is leaking or poorly connected. I have not checked voltages yet.

[whywontyouwork]

Re: Samsung un46c8000 broken board

Board with HMDI and cable inputs

[whywontyouwork]

Re: Samsung un46c8000 broken board

Main board

[budm]

Re: Samsung un46c8000 broken board

Board with HMDI and cable inputs

Main board.

[budm]

Re: Samsung un46c8000 broken board

Main board

Power supply board.

[whywontyouwork]

Re: Samsung un46c8000 broken board

Here is the power supply.

When I spoke with customer service and looked online, it was the board BN94-0296F that was replaced for this issue. It is the blue one I posted.

[mmartell]

Re: Samsung un46c8000 broken board

Put a hair dryer on the main processor (on the main board) for about 30 seconds and then try to power it up and see if the symptoms get better, worse or no change.

[NBE1]

Re: Samsung un46c8000 broken board

Just joined while looking for info and thought I would pop in and give my 2 cents. Definitely try freeze spray/upside-down compressed air, heat, and even light physical pressure on components in question (except for when touching it would be dangerous). In my experience with my sets, the IC that controls HDMI is bad. This is assuming all your voltages check out. But as has been stated before, troubleshooting and work on mainboards is pretty complex. Without a few proper tools and a little help you have a high risk of seriously jacking up the board, especially if you're new to electronics in general. I only say that because that is what I did on my first repair, but you may be a better man than I. At any rate, it is worth a shot if it is going in the trash. Or if you plan on buying a new main anyway. GL