philips lcd tv powers on ok backlight on sound on no display

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

ok with both ribons connected i get these results

vgh-m 7 mv millivolts
vgl 5v
vgh 12v

does this mean anything

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

i guess this tells me the main is working and tcon is working since im getting good voltage without cable connected right?

but once cable is connected the voltage changes due to panel issue ? or is the drop normal?

[budm]

Re: philips lcd tv powers on ok backlight on sound on no display

It looks to me that the bad section of the panel loaded down the Voltage.

[Shinju]

Re: philips lcd tv powers on ok backlight on sound on no display

Yeah, you can see how bad the damage if any is on the bad side of the tft board.

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

so on a good tv with both ribbons connected these voltages should be high like they were when right cable not connected.....on my tv?

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

ok so when i had the right ribbon off the voltages were good so the left side had a good pic.....and right side white since not connected...but when i connect the right ribbon since there is an issue apparently on that side of screen it draws volts down so that there is no pic on entire screen?

[budm]

Re: philips lcd tv powers on ok backlight on sound on no display

For example of the VGH (23V or higher), VGL (-5V)
https://cdn.badcaps-static.com/pdfs/...ed07295066.pdf
Your board uses TPS65162.
https://cdn.badcaps-static.com/pdfs/...f85ec7ae25.pdf

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

and since i do ave good voltages without right connected that means tcon and main are good?

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

yeah and my vgh-m went from 26v to 7mv

[budm]

Re: philips lcd tv powers on ok backlight on sound on no display

Your VGH also went down to 12V.
See post 67 for the spec of IC used in your board.

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

yes vgh went down to 12v and yes i saw post 67 says 23v and higher....so im going to agree that panel is bad on that side as you sated from start.......this does help me though for future troubleshooting.....such as my sharp 60 inch with same issue backlihgt on sound on no display.....does the vgh vgh-m and vgl appply to all tcons?

[budm]

Re: philips lcd tv powers on ok backlight on sound on no display

"does the vgh vgh-m and vgl appply to all tcons?" Yes, the VGH and VGL are present in all the T-CON for the LCD panel, not sure what the VGH_M is exactly, but the bottom line is that they should not have dropped down like that.

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

ok thank you

just took tv apart down to panel....do not see any visible dmamge to right side tft board......

no discolorization or any visible signs of liquid

is there anthing i can do such as tapping something or anything to see if it helps?

i did try tapping the board and powered tv back on and no change....this sucks

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

oh one more thing.....can i test the tft board for short in any way?

if so what would i be looking for as far as testing points

thanks

[shelby5041]

Re: philips lcd tv powers on ok backlight on sound on no display

hi budm..ive been messing with tv a little but for some reason now when i disconnect the right side ribbon on tcon i dont always get a bright display on left side..sometimes it goes bright blue and then on screen display is fine and sometimes it stays dark with a dim image of on screen display........i checked the voltage when it does this and the tcon voltages are good like 26v 26v and 5v....and the backlight is on.

....when the left side is dim with an image the right side isnt as bright white as it was....earlier when i got a nice bright blue background with on screen display but this all started happening when i took the whole tv apart...and half put it back together to test the display again...everthing is connected and secure

now im really confused ......im wondering if its because since i have the tv kinda of disassembled and i only installed boards back using 1 screw on each one that would be an issue...ground??



i guess