Sony XBR-75X800G - Android start up only and dark blue screen

[nomoresonys]

Anyone paying attention would have read in post #22, that there is 120 v at the wall outlet and nobody needs to carry a tv to another outlet when an extension cord can be used.

[NolesFan]

Had the TV off all day, came home and was still reading 66.7. Wall outlet reads 123. If I plug the cord in to the outlet, but leave it out enough to get my probes on it, its reads 121. To satisfy Davi, I went to another outlet across the house, metered it: 121. Plugged in an extension cord, metered it: 121. Plugged tv to said extension cord, metered harness plug-in: 64.7, metered main fuse on PB: 64.7.

Well seems Davi was right though. After metering things, I left the TV on and about 10 minutes later, it reverted back to the dark blue screen. Sound plays fine, though this time, I can use the remote to talk to tv and it talks back, when I press the presets on the remote the picture changes in brightness then returns to the dark blue. So Im assuming go back to original testing as described before the "fix" happened, but the question now is, will i get accurate reading at the terminals if I dont have 120 entering the TV?

[nomoresonys]

Seems like the power cord is ok, can you explain exactly where and how you are measuring 64, how is meter set and where are you putting both probes?

[Davi.p]

So i was NOT right.. the wall outlet is not the culprit but maybe the house cabling yes (??).. seems as a cable somewhere has a clamp, maybe due to oxidation, that when the tv is standby or cold the current is enough but when that cable heats the voltage drops.. i don't know how long is that extension cord but if is possibile it can be attached some way directly to electrical breaker for a test..

anyway due to the fact the tv is sold as bad, the answer could be inside it, so the huge loss must produce heat, when tv starts to have problem must feel that heat precisely, or since the drop is immediate the heat also can be felt immediately..

[NolesFan]

No, you guys were right, the metering was only ready 1 leg with the way I had it set. Correctly now metering both legs and I have 121.7. Sorry for the confusing on my part.

So now I with the correct voltage entering, I will run thru the tests you guys suggested. I appreciate the patience.

[Davi.p]

In USA things are very different than Italy.. here there are professionals that uses 5$ testers (very bad) and there there are absolutely beginners with 100$ testers.. very strange the world..

plus here a 75" bad tv but integer needs around 200/250$..

[nomoresonys]

Don't we all know by now that Europe has 220v and North America is 120v. Been that way for a very long time.

[NolesFan]

Diah

I bought some pin jumpers from Amazon to link up the 4 pins you mentioned ( 5 - 7 - 9 - 26 ) but they are too loose. What type of jump wires are you using to test things? When I pull the harness off the PSB, Im left with male ends. I cant get a wire to sit there, alligator clips are too big, and like mentioned, I bought female test ends to push on but they are too big for male pin and just fall off. I tried leaving the harness plug in on PSB and using male pins, but when I did the asked configuration, the TV wouldnt power on, so I figured I wasnt getting a good connection with the pin set I bought.

Also you mention 1KR, Im dont know what that refers to? I am able to figure out which is which because I can see on the board the 1 and 2 respectively designating which row is odd or even.

Any help with names of jump wires or links you can provide to purchase a good set of test leads would be awesome. Or if you can point me in the direction of what to use that works best, that would be awesome also. I really appreciate any help you can give in the matter.

If when I get this configuration all correct and I do get an image on screen, then Im guessing its the MB that is what is wrong?

[vinceroger69]

1kr diah means 1k resistors used for jumping pin to pin

[NolesFan]

Thank you vinceroger69

So I ordered new jump wires that are smaller on the base to allow less interference, but in the meantime, I was playing around with the harnesses again and the picture came back on. It was that was for 2 straight days. I went to move the TV ( its standing on its base ) and when I shifted the TV and set it down, i lost the picture, but the sound to what I had playing on Youtube is still playing. Is that type of issue leading anyone to believe its definitely the MB or I still need to wait to get the jumpers and run the test in post #14? Thanks

[nomoresonys]

Do that wiggle with the harness, starting to think if you get a good picture after messing with it sometimes, you may have a wire in it that only gets connection sometimes, you can test continuity of each wire form end to end with meter, want to be careful not to stretch out the ends of connectors with meter leads. I use stripped bread ties sometimes to poke in the ends to make connection for testing, then wiggle the harness, each wire should maintain continuity if one doesn't then it's a bad/broken wire.

[nomoresonys]

Also if you have not yet, make sure you don't have any bad solder joints on powerboard, just search for images of bad solder joints if needed.

[NolesFan]

nomoresonys Ok, Ill check that along with #14 post. But since I wrote and you wrote, I went out to TV, still have it powered on, unplugged harness at PSB to the MB and plugged it back it, the TV booted up with Android screen and is now back to Home.

[NolesFan]

And now at this point, I can turn the TV and it will show normal picture, work for a few hours then go dark blue. I can shut off the TV for a little while, turn it back on and its a normal picture again. Leave it on a few hours and itll go back to dark blue.

[Davi.p]

it seems a common problem at the lcd panel, alternate short to a condenser, must do the screen self rest.. remove lvds cable from MB, jumper a 12v from PSB to tcon fuse, turn on and see full screen colours for the time to eliminate doubts..

[NolesFan]

its much likely Main Boards... but because you have dark blue picture, you need to testing the screen as standalone, if every things went correct then replacing MB.. you will not able to repair the boards. as its just ONE Soc ,
to do screen standalone test ..
disconnect the MB from PSU
disconnect the LVDS between T-CON & MB from T-con side
on the socket of the PSU, you need to jumper
Pin 5 STBY_3.3V to PIN 9 Power_ON & pin 7 BL_ON & pin 26 T-CON_ON check the pins No. you have print chart on the boards... it may my memories went weak

take 12V from the pin 25 T-CON VCC and put it on the F fuse on the T-con
put it in wall and check what you will have on the screen..

Note if you are not sure by pins name or No... use 1KR when you do the jumpers to avoid any damage to PSU in case you did wrong at pins order

Note 2 you can do hard reset from plug it out from wall . press joystick and push down then plug in wall leave the push only when the front LED change from white to green

Well i tried this with the new jumpers I got and the TV doesnt respond. When I plug it into the wall, I hear the initial click of the PSB but the remote or the joystick does nothing as far as turning on the TV. Im guessing its my connections with the jumper? Because as soon as I pull the jumpers off and plug the PSB to the MB, the TV comes on.

[Davi.p]

how can you jump a single pin to others inserting jumper wires? You need a side without pins and twist copper together.. check the pin outs for correct tensions..

[NolesFan]

how can you jump a single pin to others inserting jumper wires? You need a side without pins and twist copper together.. check the pin outs for correct tensions..

Jumped from PIN27 TCON_VCC12v to Fuse on TCON. Plugged in, turned on, TV went thru its loading as far as back lighting, but the screen stayed dark blue. Android start up sound played. I verified I was getting the 12v to the fuse and yes I was get 12.+ volts

[NolesFan]

Again today
connected Pin 5 STBY_3.3V to PIN 9 Power_ON & pin 7 BL_ON & pin 26 T-CON_ON. At the connection of all 4 wires, had a reading of 3.57
connected 12V from the pin 25 T-CON VCC and put it on the F fuse on the T-con, had a read of 12.51 at the fuse.
Plugged TV into wall, I got one click.
After that, the remote or joystick was unresponsive, TV would not turn on

[Davi.p]

OMG....tv must not turn on normally, main board is detached and isolated, cannot load any software, only tcon circuitry must run, must cycle full screen colours.. is a self test built in the tcon.. tcon is likely be ok, panel maybe is ok, but panel circuitry can be shot, since no load is.present on the.main board cable, maybe 12v rises a bit more and shorted component goes full short, two ways now, check panel strip boards for bad caps, or put a resistive load on the 12v to lower.it and retest screen..

sorry, third way, an.ATX power.supply can provide around 10,5v when using only the 12v output, can.use.it to power tcon, for the backlight you use the normal PS board with jumpers