Mert1177 said: I have replaced my two Convergence IC's and have checked all the fuses. Ended up replacing one Pico fuse on the "G" board. After re-installing both the g board and the d board I have found that the blue is perfect while the red and green are still giving the "bowtie" effect. I have been able to adjust the green vertically but not horizontally and the red does not move at all. Would you be able to tell me what is wrong and how I can fix it?If and I do mean if all of the fuses etc are ok and the supply voltages are ok to the ic's, you probably have a faulty ic. Also if you are using after market ic's, the reliability is not as good as the original.
Categories: Televisions and Projectors
There has been a large amount of chatter on Techlore about Sony convergence ic problems. Luckily Most Sony projection tv's no matter what model you have should be similar to my explanation below, Since Sony rarely fully re-engineers a tv what I am about to say will apply to most Sony projection TV's. A service manual is generally not needed to perform the repair.
WARNING! If you don't have any electronic experience this is not for you, I assume no liability for any harm that may come to you or your tv. Perform this procedure totally at your own risk. High Voltages exist in your tv and on the boards I am going to talk about, and can have high voltages on them even after the tv is unplugged.
What has happened to your tv:
What has normally happened is that the convergence output driver ic's either one or both of them has shorted. Causing your picture to be un-converged, The Symptom of your failure can take on many different looks, so one explanation of what the failure looks like will not be adequate. It will be basically one or more (red,Green,Blue) crt's are not aligned correctly, and colored shifted, and distorted picture of some kind will be seen. Auto focus will not fixit and may even make it worse. When these ic's short, they can cause one or more pico fuse to blow. Allot of people ignore this part of the repair and get themselves into trouble. Please listen to my warning, and make sure you check these fuses!
About the boards:
The two boards we will be working with are the "D" and "G" boards. They will have a big "D" or "G" stamped into them. On most models the "D" board will be to the center left of you when looking from the back. The "G" board will usually be to the left of the "D" board and standing vertically. When removing the board make a mental note of where all the plugs go. The Flyback (the big gray transformer near the back) has a fat red wire coming out of it. To remove this wire push down and twist on the distribution block side. Don't try to remove it from the flyback side, you can damage the flyback. There is a focus wire going upto the focus block as well, pull the wire straight out of the focus block side. But if you have enough room to work behind your television you can leave the red and focus wires in the tv, just flip the board over at the television after removal.
The parts you will need are two ic's that are referred to as STK ic's. This is in reference to the first three letters of the part number. You will also need some pico fuses. The pico fuses are little yellow fuses that look like resistors. When they blow, they will show no physical sign of failure. The amperage rating will be printed on the fuse. For example a 5 amp fuse will have the number 5000 on it. A 3.15 amp fuse will have the number 3150 on it. You will need to use an ohm meter to test these fuses.
The Location of the parts;
The stk ic's are on the "D" board, attached to large heat sinks, When looking from the back you can see the heat sinks but the part's themselves will be pointing away from you and hard to see without removing the board, or using a mirror to look at the part numbers. The fuses are generally located under the fins of the heat sinks. There are several of them and vary by model. On the "G" board there will be two yellow pico fuses near the connector going to "D" board. These fuses provide power to the stk ic's you must check these as well.
When replacing the STKs make sure you use heat sink compound on the back of the ic's before installing them. Also as a rule of thumb, screw or clamp the ic's down to their heat sinks before you solder the pins. Replace any blown pico fuses and re- install your boards. When you turn your set on it may still be out of convergence due to many factors. Try pressing the auto focus button on front of your set. If this does not work, you will need to do a convergence. Please see my article "Sony Convergence Procedure" to complete this part.
Possible Problems after the repair;
Many things can happen during your repair, the most common problem and one that even I - an experienced tech still have problems with are not plugging in all the wires. This will cause various strange problems. So if the set acts differently than It did before. First suspect that you have missed a wire. Don't assume that you got all the wires in. it is extremely easy to miss one. I have had people and techs tell me "I am sure I plugged in all the wires" but when I investigate a little further we find that wire that was hidden behind something else and once we plug it, all will be well. Another issue you need to be aware of is if you are in convergence mode and you cannot move one of the colors in either vertical or horizontal directions. Re-check you pico fuses and solder. 99% of these problems are due to either shorted pins or a missed pico fuse.
If you have more questions about this repair, start a conversation on this board and I will help you with your question. Please include the model number of the set so my responses can be specific.
Read More In: Televisions and Projectors
I see technology only after the chalk outline has been drawn on the floor. Follow me through the word of repair and learn the gritty truth about technology.
What tool are you talking about Rocky1918? I simply disconnect the larger wire coming from the transformer and going to the high voltage block from the High Voltage distribution block by pushing down, rotate the wire counterclockwise. It will come out. Never heard of a special tool for that.
"Those who do not know their opponent's arguments, do not completely understand their own".**For complete TV repair kits including parts goto www.TvRepairKits.com
Response to my previous posting -- I replaced the convergence IC's and have the picture back. I was able to remove the high voltage cable from the distribution block with out the Sony tool, had to push in and twist in both directions, gently of course, and was able to get the larger cable out. I was not able to get the smaller cable out but had enough room to work on the board.
Advice on taking off and reinstalling. I filed the point of my soldering iron down to a very fine point and used a solder sucker to remove the solder. The pads of the IC are very close together so when you remove them, they did not take much heat to remove.
As for putting back in, use a lot of light, a magnifying glass and a small amount of solder for each pad. I double checked the pads and had someone else check to make sure there were no bridges between the pads. Good Luck
tech_john said: I was able to remove the high voltage cable from the distribution block with out the Sony tool, had to push in and twist in both directions, gently of course, and was able to get the larger cable out. I was not able to get the smaller cable out but had enough room to work on the board. Advice on taking off and reinstalling.
Just and FYI, On my set I didnt need a tool for the larger wire, just pushed and turned 90 degrees. As far as the smaller wire that goes to the front of the set, that one just pulls out, no pushing and turning required. I only say this because it can be hard to solder from behind the set.
Best of luck to all of you!
I could use a little help. I was having trougble with the blue convergence line on my sony kp 61v45. I replaced both ic chips with the 392-150. After replacing the 1st one, I checked the set and the picture appearred, still w blue out of line. After replacing the second one I get no picture! I hear static from the audio and get a continuous blinking red light.
zapdbf-I re-checked all wires and solder joints. Do you think i should take out the last ic and put it back in. I had 2 capacitors and another item that needed to be removed so i could pull out the ic. Do you think it's likely something else ewnt bad after replacing the ic's.
no i didn't check the fuses-the pico fuses ? i guess i need a multimeter to check those, right? please advise on how& what to test.
zappdf this is geras im waiting on youre respond for the blue i mage on a sony tv?dont now if you still remember? i did change the blue wire with red and got red picture.
whats next or replace what?
Mert1177 said: I have replaced my two Convergence IC's and have checked all the fuses. Ended up replacing one Pico fuse on the "G" board. After re-installing both the g board and the d board I have found that the blue is perfect while the red and green are still giving the "bowtie" effect. I have been able to adjust the green vertically but not horizontally and the red does not move at all. Would you be able to tell me what is wrong and how I can fix it?there are six pico fuses on the convergence board by the the heat sinks to check (the D board) and I believe two fuses on the power supply board (the G board) + and - supplies. If they are ok sus pect bad eeprom its on another verticaly mounted board look at service manual if possible
Hello ZAPDBF-By the way i want to thank you for your help and this site. I think it's great you can help us save some serious cash and in my case, i would probly never have had it fixed..
I'm back with my meter. I tested two pico fuses, found one bad. My set,kp-61v45 has the 2 large heat sinks on the g-board, which lies flat. The pico fuses are toward the center of the board. I located a "regular" fuse by the power supply which is good. I looked at the other board,rght of g-board, and didn't see any fuses. I was looking for pico or "regular" fuses. Pls advise.
ZAPDBF-thanks, but are there other fuses? I can't locate any other fuses
zapdbf said: Yes on the "D" board aswell, look around the heat sinks for the stk ic's
zapdbf--I was thinking maybe my setup was different, my ic's are on the g-board, which lays flat. I did locate 2 picos there. The board to the right of that one also lays flat and i couldnt locate any picos on that one? pls advise.
ps are those pico's fast or slow blow?
zapdbf--thanks for clarifying that. i did change both. At first one tested bad, one good, after replacing the bad one, the other tested bad ?? Still didnt work, no picture. So I took out the 2nd IC that i put in, replaced it with the 1st old ic i took out, and wha la, I got picture. For some reason I had a hard time removing the solder from the components. I used wick and a solder bulb. I use a 15 watt soldering iron.
1. should i be using a 25 watt iron?
2. is it safe to leave in the old ic (if my convergence issue is fixed-can't find the remote now)? Old ic is a stk392-110, new is 392-150?