Sony KDL 48W600B Picture goes away, sound and backlights still work.

[DesertRat]

This one is a funny one, to me anyway.. The TV turns on and the picture is there for a couple of minutes at most, you can navigate to "Help" and shortly after that it fades out. You can continue to navigate as you can hear the "click" sounds as you navigate, the back lights are still on too but the picture is gone..

I'm including the picture of the back opened up. It's not a closeup but let me know if you need one. And the line you see in the image is in the camera, not on the board.

Any ideas?

[ghoshiry]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

hi dear
checked your LVDS cableflat
tanks

[dick_barton]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Does this model have a Tcon board similar to attachment?

[koka0011]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

i guess gamma ic is not good.before that clean the lvds cabel.

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

hi dear
checked your LVDS cableflat
tanks

i guess gamma ic is not good.before that clean the lvds cabel.

Thank you ghoshiry, and koka0011, I will check the cable and clean it and see if that helps. And I'll keep the gamma ic in mind as potentially not good.

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Does this model have a Tcon board similar to attachment?

I don't see a Tcon board in it. It looks like it feeds off the main board. I'll post another pic shortly showing a ribbon cable connection (both ends).

I also need to make a correction on the model. It's not a KDL 40W600B but instead a KDL 48W600B. I know that may not make a lot of difference, but sometimes it does. Sorry for the confusion on this.

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Here is the only ribbon cable I can find. It looks to go from the top of the main board back behind or under the back of the main board, down to the other red arrow where it connects to what looks like a small circuit board that is about as wide as your finger.

[irad]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Blow air onto the main board. Move the airflow to different spots on the board where the square ICs are located. If the picture comes back you need to add a cooling fan. I suspect the gamma chip is going and is getting hot.

[dick_barton]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

To the RHS of the LVDS cable where it is marked F8001 there is a small black transistor/mosfet. Can you measure the voltage on the 3 pins with black meter probe to chassis when you have a display and after it fades away.

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Blow air onto the main board. Move the airflow to different spots on the board where the square ICs are located. If the picture comes back you need to add a cooling fan. I suspect the gamma chip is going and is getting hot.

Is the gamma chip the one that says "Sony X-Reality Pro" on it? It appears to be heating up. Will try to cool it down or transfer the heat some way and see what happens.

To the RHS of the LVDS cable where it is marked F8001 there is a small black transistor/mosfet. Can you measure the voltage on the 3 pins with black meter probe to chassis when you have a display and after it fades away.

I took readings before and after, here they are:

Orientation from top view:
1 being the top connection by itself
2 being the left connection
3 being the right connection

Before:
1=12.43
2=10.49
3=12.44

After:
1=12.49
2=10.54
3=12.49

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Something is definitely warming up (most likely the gamma chip possibly failing as has been suggested). I put a fan behind the unit and aimed the brunt of the air at the main board and was able to "surf" through the general information on the set itself. That's something I haven't been able to do. I ran a self test and it found no errors and I could see and hear the test of the audio and video portion of the test. It has been shutting the video down before it gets started good. I was also able to navigate around for some time after the test. So it looks like we're on the right track.

[Diah]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

did you feed it with signal? and from which source? test with out signal are nothing for this sony

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

did you feed it with signal? and from which source? test with out signal are nothing for this sony

I hooked it up to a TV antenna signal (OTA) and was able to get it programmed for channels, but then it blinked out again. The channels are saved and I can surf through them, but it still fades out after things heat up again. Is that what you mean by a signal?

[vinceroger69]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

maybe get a proper can of freeze spary and narrow down the faulty part yes you can use air duster but i have a proper can of electronics freeze spray for jobs like this seems too freeze/last a lot longer on the ics.

[Diah]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

I hooked it up to a TV antenna signal (OTA) and was able to get it programmed for channels, but then it blinked out again. The channels are saved and I can surf through them, but it still fades out after things heat up again. Is that what you mean by a signal?

Okay, you need now to take out the RF board from the main board, then turn on and tell the result.

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

The only IC that's getting warm even is the "X-Reality" chip. It isn't getting hot to the touch, but it is warm to the touch. The other chips on the board are cool to the touch. I don't have any freeze spray or air duster.

Before when I had the fan on it, it was in a cooler part of the house and it's a pretty good sized fan. It's one of those Lasko floor fans with the squirrel cage. It can move some air, and the fact it was cooler probably helped too.

I just had the TV on, and it lasted about 3 minutes before fading out, with no fan on, and on an analog channel (not sure if that would matter).

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

Okay, you need now to take out the RF board from the main board, then turn on and tell the result.

I get a red blinking light that blinks 9 times then stops, then starts blinking again to repeat the error code.

[Diah]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

okay, put it back and run diagnostic, after that reset the TV to factory, and install your OTA again

[DesertRat]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

okay, put it back and run diagnostic, after that reset the TV to factory, and install your OTA again

Got to the discovering the OTA channels, and it faded out again.

[Diah]

Re: Sony KDL 40W600B Picture goes away, sound and backlights still work.

also after you finished from the above go to the side of SONY and download the last firmware 9/27/2016 PKG3.001A
https://esupport.sony.com/US/p/model...d#/downloadTab