Baird 55 inch uhd no display

[finntricky]

Ok guys, got this tv as none working, got it home plugged it in and it fired up with no problem, used it for a week and then image disappeared, still boots up ok and stays on with back lights but no image, I'm getting correct volts from PSU to main board and back once turned on, next thing I check is fuse on tcon and that is fine, then checked the volt readings on the output side of the tcon. Got some strange very low volts, so got another tcon put that in and still getting low readings, think I may have a main board prob

[nomoresonys]

Re: Baird 55 inch uhd no display

Maybe unhook the tcon ribbons from panel, see if you have same readings. (best policy is to do all connecting and reconnecting of such with tv UNPLUGGED)

[finntricky]

Re: Baird 55 inch uhd no display

readings from the tcon, all seem to be the same with or without ribbons, now checking buffer boards for shorts, tryed removing one ribbon at a time, but still no pic on any half of the screen, seems strange that i picked it up in this condition, pluged in when getting home and it worked,

[neilc6]

Re: Baird 55 inch uhd no display

12V for the tcon is usually switched from a small FET on the main board. Without a schematic, you will need to trace it back. The 12V supply may be supplied by a few lines on the edge of the flex cable.

[finntricky]

Re: Baird 55 inch uhd no display

I get 12 volts on tcon and get the correct readings marked on the output side, just checking a winbond chip on the buffer, trying to find some info on it, but only finding flash chips, it's winbond 25Q16DVIG

[dick_barton]

Re: Baird 55 inch uhd no display

It is a serial flash memory IC
https://cdn.badcaps-static.com/pdfs/...ba94e02774.pdf

[finntricky]

Re: Baird 55 inch uhd no display

just read though that, and not sure if i understand, thanks btw,
so on VCC i get 3.3v, HOLD 103 i get 3.3v, CLK i get 0v, 100 get 0v,
CS i get 3.3v, 101 i get 0v, 102 i get 3.3v, this is when tv is turned on, is this correct ?
or is this where the fault is, can't find any shorts on buffers or faulty caps

[finntricky]

Re: Baird 55 inch uhd no display

it would seem that everyone is as at a loss to this problem, so i gave up.

[dick_barton]

Re: Baird 55 inch uhd no display

You really need to use an oscilloscope to check the IC. A meter is virtually useless for this task other than checking VCC and Ground. The clock frequency would be too high for a meter to give any meaningful readings up to 104Mhz.