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Did the TV suffer any kind of damage, e.g. from a power outage or thunderstorm?
Were all of the replacement boards new or used?
Approximately how old is the TV?
Thanks for the detailed information, it is helpful.
Were all boards replaced at the same time, or one by one?
If there was a short on one of the original boards (e.g. on the T-Con or Main board) and it caused the Power board to blow, then if you had simply gone ahead and replaced the power board, it may have blown again.
To troubleshoot further you will need schematics and some electronic test equipment, to follow the circuit and locate the fault.
If you need a copy of the service manual, it is available from:
Yes it is possible that some of the boards have been damaged if replaced in that order.
To find out, you will need schematics and some electronic test equipment, to follow the circuit and locate any faults.
Apologies for any confusion - I mean you will need the circuit diagrams, not the layout, as you will need to debug at component level if you wish to troubleshoot further. Do you have the circuit diagrams for the boards?
Indeed it is; however the fault will not be located there - it will be among the thousands of electronic components across the various boards.
No; sorry if I am not being clear - what I am trying to say is that each board needs to be tested at component level first to determine if it has shorted out and is going to blow the other boards, then once you find the faulty board it can be replaced.The only way to do this is by testing at component level using test equipment and circuit diagrams.
Hi, just checking in on your question, do you need any further assistance?
I'm sorry to hear you are having a problem with my answers.
I will opt out of your question and another expert may be along shortly.
Hello Gary, I'm Shahid. Sorry to hear that you're having trouble with this but I'll do my best to help. Please reply back if you still need assistance.
Yes, I can see previous conversation in this thread.
Just to clarify, TV power light is still blinking 3 times, correct?
Thanks, ***** ***** power light flashing indicates audio error and possible cause is shorted speaker or wire connecting speakers is touching/ crushed to metal chassis of TV (ground) and causing short.
Please unplug connector of speaker from K board, replug TV power cord and turn it On.
Does the power light still flashing 3 times?
Gary, I'm a Sony tech and have related service manual for troubleshooting purpose.
3x red flashing light doesn't indicate power board failure, however, main board could be bad, 3 times flashing error code is audio-protection.
Since you have already replaced all of the boards in TV so I requested to please check connecting wire from K board to speakers to make sure it isn't pealed off that can caused short and activate audio-protection.
Can you unplug connector from K board that goes to speakers then turn On the TV as a test?
OK, you wont get usual thump sound as long as red light is flashing which indicates TV is in protection mode.
- Have you unplugged the TV power cord while disconnecting speaker connector from K board and replug power cord back in then press power button to turn On the TV?- If so, please disconnect other connectors of K board and check again.
OK, as per website rules I'll send phone call service offer as you requested, feel free to ignore if you prefer to troubleshoot the problem here in text chat format.
No problem, we can still work here. Please give me few minutes to check the manual again.
Thanks for waiting. Have you tried to update TV firmware (internal software)?
I understand the frustration. Where did you get the replacement main board from and was that reliable source?
OK, then replacement main board should work.
Can you check 12V DC at K board coming from power supply board?
12V may appear for a second when press power button or replug TV power cord in so get ready the meter then replug power cord to see any reading on meter.
I'm working on K board image to assist you for volt reading, give me 10 minutes please.
Thanks, ***** ***** attached picture where I marked the pins of CN4602 connector with yellow arrow to check 12V.
12V should be available at pin 1&2 of that connector when plug TV power cord in.
If power light start flashing right away when replug TV power cord in then the main board is suspected and should be tested in similar model working TV as if TV turns On and then switches Off after few seconds with flashing 3 times light then it could be bad speakers, connecting wires or K board internal issue.
Can you try old K board in TV as a test?
If the red light starts blinking consistently 3 times within 3 to 5 seconds after plugging the TV in then K board or speakers or connecting cables are most likely bad and main board is least likely defective.
Nice, that means power board is working and providing 12V to K board for audio amp chips.
Please try old K board in TV while leave the speaker connector unplugged.
OK, take your time.
I'm sorry at this point as I'm out of ideas what it could be so let me repost the question for other experts to have a look and hopefully some one will respond to assist you further.
I'm opting out to repost the question.
I am very sorry. Me posting on this page was a mistake, earlier. Please, ignore my post. The website posted it on this page instead of another.
Another person will continue with you.