SamyGO

Hi,
My UA46C6900 VFXXY is playing up, and ive done some tests and believe to have narrowed it down to the mainboard.
It will click off its head, before i have to unplug it, leave it unplugged for a while, plug back in, and sometimes it will work.
Once its working, its fine... however its like playing Russian Roulette with if its going to work or not.

Ive unplugged the ribbon cable and jumpered pins 16 and 18 and plugged it in, and the backlights come on, powersupply doesnt click clack, just works with a blue screen.
All the voltages are good at that time, aswell as when it is working.

I have done a service menu reset in the past and that did nothing to help.

So im looking at replacing the mainboard, however... It seems quite tricky to find the correct board, and i have read through these boards and it looks like i might be able to buy a substitute board that would work.

It seems that the UA code might be unique to Australia, so im assuming the UE and UN are similar TV's.
The mainboard has the part number BN94-03562L and TVServiceParts.com looks like there are a bunch that might work.

http://www.tvserviceparts.com/BN94-03566A.html
http://www.tvserviceparts.com/BN94-03566B.html
http://www.tvserviceparts.com/BN94-03566C.html
http://www.tvserviceparts.com/BN94-03566D.html

It also mentions the C6800 boards are interchangeable but being a lower number (C6800) I'm a little cautious of that...

http://www.tvserviceparts.com/BN94-03514A.html
http://www.tvserviceparts.com/BN94-03514B.html
http://www.tvserviceparts.com/BN94-03514C.html
http://www.tvserviceparts.com/BN94-03514D.html

So i guess I'm hoping someone can give me some advice on what upgrades are possible, or what alternative boards might work?
I read somewhere that generally 46-55 boards will work and to stay in the same family of TV (C Series)
Does the model number matter, in that would a C6800 board work in a C6900 model?
Or should you try and upgrade the number to ensure the factory features will still be there and possibly add new ones?

Does anyone have any good sources for TV parts ? Shopjimmy doesn't seem to have stock or much in regards to these models.

The C6800 board should be ok for you, its also ok to take boards from different panel sizes. Just check that the baord has the right tuner (DVB-C / S2 /Dual...)
the 6800 / 6900 can be set in advanced service menu, i dont exactly know the difference.

Ok thanks for that.
I have a little update... I baked the main board in the oven for 10mins @ 200deg C. Last night then let it sit with oven door open for 30 mins to cool down before reassembling. It's turned on perfectly many times over the last 12 hours. And even after leaving it in the TV on standby overnight fired up first thing this morning. So this may have fixed it. I cross my fingers and will know in a few more days if it's a confirmed fix.

+1 for the "bake fix"

Now on about 3 days, hasn't missed a beat. I'm very happy with the outcome. Hopefully it stays this way. Just wish I had have done this before replacing the power supply board and all its caps. Ahh well lesson learnt