TV Repair Questions? Ask a TV Technician
Hello WelcomeThanks for the QuestionI may be a few minutes between each request for info thanks for your patience!
Could you please count the amount of blinks between pauses please like 4 blinks pause 4 blinks as an example?
There are no blinks between the click sounds. the light only flashes when the the tv makes a click sound. And this only happens, once when i plug it back into the wall outlet. And then it keeps clicking continously with about 2-3 seconds between clicks when i press the power button. and the tv never turns on.
I have let it go for roughly 15 min max to see if it will eventually turn on.
I think the TV's micro is cycling on and off, forcing the TV to click on and off. I'd check the main board's P-On line that actually triggers the relay on the power board to click on, and start up the TV's power supply. I'd also check the power supply for bulged capacitors, because the power supply does deliver 5 Volts to keep the micro running.
If it's low, it can make the micro cycle on and off. Do you have a voltmeter so you can check the 5 volt standby line and the P-ON control lines found on the power supply board?
Yes i do have a voltmeter, and thnak you. I should restate. It is NOT the standby light flashing, that was my mistake. It is the power light. it stays on and then flashes with each clicking sound. I have looked on the power supply board for bulged caps and cannot find any.
could you run me thru a step by step to check the P-On line?
Ok, you may find it faster than I can. Sony marks their plugs with plug legends, which are little boxes that name each wire. See if you can find a P-on and a 5vstby or a 3.3vstby line.
I'll look for a picture that may show it. Close up of the power supply board, 3 plugs on the corner of the board --
I have found the 3.3 vstby on the top right of the supply board and with the tv plugged in and the power button turned on, I am getting a 6.6 volt reading.
I also checked the power on pin, I get a 6.6 volt reading and when it cycles or clicks, it drops to 1.4 volt. after the cycle, it goes back to 6.6volts.
That seems high for the 3.3 volt standby....
Turn the TV off.
You see the 3.3 Volt standby on pin 5? The one next to it, pin 6 is the standby's ground as is pins 9 and 10.
Use pin 9 or 10 to see if the voltage is still 6.6 Volts DC. If so, we should see about replacing the 3.3 Volt cap, and possibly the optoisolator, possibly the drive IC too.
Do you have some basic soldering and parts replacement skills or am I jumping the gun here?
I have checked the 3.3 using pin 9 and 10 and 6, all read 6.6 volts.
I do have some basic soldering skills and understand the replacement.
reading diagrams on the other hand.... but if you can explain it im sure i can get it.
It really isn't hard. The parts I highlighted I would replace ALL of them, starting with the 470uf 16 Working Volt capacitor. The transformer is a small square box like the yellow ones in that first picture I sent. You use that to find the parts locations I listed. T6301, is fast and easy to spot, and the parts right by it are going to be listed as 6300 parts.
That cap, can probably be purchased at Radio Shack if you have one nearby, and 470uf is the capacity, 16 Working Volts is how much Voltage it can handle without popping.
Here's an example of that cap
It's like a battery in your car, you install the black band where the original's black band is located on the board.
That one will work on your TV...it's stocked at Radio Shack.
You can get that tonight and stick it in.
Look for a capacitor. The location number will be C6315, marked on the board and close to that transformer box T6301
i located C6315, and I will have to pickup a cap tomorrow after work.
I have a smallbit of confusion, the 2 links u posted. One is a 16 volt, the other a 35 volt. do i get the 16volt?
I have replaced C6315 with a 470uf 16v cap and there appears to be no change.
Thank you for all of your help thus far I have a question though.
All of the parts you outlined on the diagram, can these parts be bought from a radio shack or from sony, where does one find replacements?
Ok, since the cap did not fix it, then the logical assumption is the other parts in that section of the power supply have to be replaced to make it reliable again.
Usually on the rest of the parts....we google it. Radio Shack carries "basic" parts, and part warehouses like MCM and Encompassparts.com are the major suppliers of unique parts.
Newark...Mouser....Allied...they are the major suppliers for the USA too.
MIP2H2 and PC123Y22JOOF can be copied and pasted into google to get suppliers.
While I would test the resistors around the PC123Y....I doubt they are off value. That part feeds back the voltage the MIP2H is creating, and since your 3.3 V is 6.6 V, you've lost control of the MIP2h2...try to replace both of those parts.
Otherwise, consider replacing the power board. Costs more, but you don't have to do the technical analysis or soldering, or anything. It's plug and play versus time and thinking/analyzing and researching.
You're more than welcome, and God bless you.
I installed the new power supply board i received, and my tv is still doing the same thing.
I noticed the standby light on the front does not come on at all. would that do anything?
I cant see that both of these boards would have the same exact problem...... any ideas?
No light at all??
The only other thing that would stop the light from lighting would be the TV's computer.
The power supply sends a standby (3.3 or 5 Volt) voltage to the computer to keep it running, then the computer sends back a Power On command to the power supply to turn on the rest of the power supply.
If the light doesn't light up, it's because we are missing the standby voltage or the computer is dead and not sending out the P-ON signal to the power supply.
You did state this --
when i depress the power button i hear a click and the standby light flashes the same time as the click sound
The relay and the flashing light told me the TV's computer is working because that is what the P-ON line does....makes the relay click.
Any lights up front are lit by the TV's computer, doesn't really matter which one lights.
But now you get NO lights when you press the power button.
I'm thinking it would be best to re-install your original board and see if the board still behaves the way it did.
If it does.....then something isn't right with the board. Sony makes it virtually impossible to plug the cables into the wrong plug, but maybe you missed one??
I've done that...the needed wire slips under a board and I don't see it. Check the obvious first, then swap the boards and see if it still acts the way it did.
So your NEW board flashes the light and makes the relay click too??
I thought you said it was dead.
Ok, thanks for the information.
I think we may have to retrace our steps first...are you getting the 6.6 volts on the 3.3 volt standby line, like you did on the old board?
Is is STILL dropping from 6.6 to 1.4 volts when the relay energizes?
Next, let's see if we can jumper the 3.3 Volt Standby to two other pins by disconnecting that supply wire from the TV's main board.
We're going to become the TV's microprocessor and turn on the power supply board and backlights to see if the relay stops clicking.
Unplug these two cables on the BU and AU boards then jumper the plug holes seen in this picture.
I gotta go to bed....I fell asleep 3 times marking up this picture. I'm totally gone....
Ok, let's Assume....let's Assume the power supply board's schematics are wrong, and it's supposed to be 6.6 Volts instead of 3.3.
Since both boards seem to regulate at that voltage, let's just Assume the schematics are incorrect because Sony farmed the schematics out to some Chinese company, and they use 6.6 Volts to drive the circuits and .....
So, let's try jumpering the 6.6 Volt line to the Relay and Power on lines, see if the relay stays turned on, and we get the 18 Volt supply that drives the LCD lamps.
If it doesn't click like crazy, then reconnect the plugs and monitor the Power on line, or the 18 Volts and see if it's switching on and off. That would indicate the TV's BU or Main board
That's ok, I was asleep at 11:18, so I hope you didn't wait for a response until this morning.
The way I would do it is this...
The power board has to be separated to test it....not removed, just unplugged.
I would leave the cables connected to the power board so I can use those to stick jumper wires in. Usually I have a toolbag full of left over capacior/resistor legs that I've cut off and a set of alligator jumpers to jumper the cables and force the power supply on.
I got a picture that drives the concept home --
I think 1/2 watt or 1/4 watt resistors fit most plugs, and you can even go so far as to get a LESS than 1 Ohm resistor (0.1 to 0.7) if Radio Shack has them. That way you stick one leg in each hole, (on the U connection) and run an alligator jumper to the Standby voltage supply and stick another resistor leg in that hole. See the most favorite....you do that on the plug with the Power on/Relay on wires, then you jumper to the standby voltage on the other plug using the 2nd favorite jumper in that picture
That's ok, that's normal...the power supply board is now turned on.
It should be delivering 18 Volts DC on the 18 Volt lines right now. Measure one to ground and see if you got 18 Volts steady.
You can check one of the other lines if you like....the 10 volt may be more convenient to measure...
Either way, we pretty much Know the power supply stays turned on and doesn't click, and it can deliver the voltages to power up the boards.
Now we go back, plug the cables back in on the plugs, monitor the PS ON or Relay lines to ground and turn the TV on.
I suspect the Relay on voltage will pop up and down, up and down....
But does the Power on line also do that?
I have seen TV microprocessors shift their command line voltages up and down, so I'd check it, verify it, and then order the TV's Micro board and replace it.
I now understand why I had so much confusion with the volts readings....
I had my multimeter on AC volts and not DC volts.
BUT before you fall out of your chair, I went back thru ALL of your instruction with my multimeter set proper, I am getting the right volts now.
SO I went ahead did the jumper again, I am getting a steady 18 volts and the only pin that fluctuates is the 10.5 V pins. Also I can hear a slight pop sound coming from the speakers. It has the same rhythm as the clicking did, and the 10.5 V fluctuates when I hear the pop sound. I assume that is the relay switching?
I am just curious which board is the Micro Board?
Again I have to thank you for taking all this time to help me with this. I am very glad I was able to finally find someone so helpful.
The pop you hear in the speakers is the power supply voltage rising/dropping.
It can happen if the power board is being turned on and off.
Now this is KEY --
IF you had jumpered the pins on the power board to MAKE it stay turned on, and the voltages are fluctuating/speakers popping, the power board is bad.
IF you had the MAIN board connected and they were popping, you need to separate the MAIN from the POWER, using the jumpers and see if the power board is still making the speakers pop or the voltages are fluctuating.
When you jumper the Power plugs....it isolates the Power board 100% -- you either have good voltage coming off the power board or you have bad voltage coming off the power board.
I had all the cables unplugged i could find other than the 3 on the power boar, jumped pins 2-4 and then over to the 3.3 stdy like in the diagram you sent me, and had no poping sound.
now when I hooked up all the cables I kept the jumper in place. Is that right?
And thats when i heard the popping sound.
Hooked up all the cables, yet you had the jumper in place?
If you hook up all the cables, you actually REMOVE the jumper, then you test the P-on line first to see if it's jumping up and down voltage wise....then you test the BL-on to see if it jumps up and down.
The point is this. You jumpered your Power board. It stayed turned on. Your voltages were rock solid....unchanging. Your 18 was 18, your 10 was 10, your 5 was 5.
That's a good power board.
You should even see your LCD panel light up....not show a picture, but the lamps should light.
Then when you remove the jumpers and plug it back into the MAIN board....you monitor the Pon line first when you press the front power button.
If it's going Hi Lo Hi Lo Hi Lo....that's a bad main board.
The same thing MIGHT occur on the BL on line, but the P-on MUST stay HIGH or ON before the BL-on can even activate.
So P-On is the KING of TURN ON.....BL-On follows behind him...
Hello, i apologize again for taking so long to reply. Farming this time of year is extremely hectic....
OK, so I did as you described and removed the jumpers and checked the Pon line. It IS fluctuating going Hi Lo Hi Lo.....So it would seem I have a bad main board.
Now, which is the main board and what does it look like so I can order and replace it?
Thank you again for being so helpful.
Just getting up to speed here --
Power board replaced, TV still clicks on/off. Both boards have 6.6 Volt standby, and P-on is going high/low/high/low.
Let's find the P-on command line and its' source. It's the BU board.
Part number -- A-1183-828-A
Location of board in TV set --
Attachments are only available to registered users.
Sites you can buy the part at --
Those are the ones I found have them in stock.