Hi to everyone, this will be my first post.. my name is Steve and I live in Hampshire, UK and I have been lurking for a few days and reading lots about my possible problem and its solution but I am a little doubtful as to the actual failure point of my 7 year old TV.
It is probably worth mentioning that about 5 years ago (ish) it did suffer from sparkles (red) at the top and bottom of my TV and after having read about it on the net, I adjusted one of the two pots on the board BUT I used the picture quality as a basis for the setting NOT any voltage reading as that was not mentioned at the time. This may have resulted in the wrong voltage settings which in turn may have caused my current problem.
So, to my current problem ... from the top, I turned the TV on two days ago and the picture was distorted and flickering for about 15-20 seconds, I thought it was the broadband/cable signal so changed over channels and still had the same problem. About 5 seconds later the picture went off completely but the sound remained. There WAS NO POPPING sound or other symptom. I tried to bring up one of the menu pages but to no avail. I concluded that the picture generation function of the TV was broken.
I then spent about two hours on the net reading various similar stories before deciding to at least have a think/go at repairing it myself.
I removed the back of the set then checked the two T4 fuses on the YSUS - one had blown. I got a replacement 3.5 amp fuse (all I could get on a late Friday night) and installed it and tried again... The TV powered on (no picture though) and I noticed about 4 led indicators lit on the main board, about 2-3 seconds later there was an arcing type sound for a few seconds then a click (?relay?), the TV turned itself off and all but one of the led indicators dimmed until they were out completely. I turned the TV back on again and the same thing happened but without the arcing sound. The fuses are still (all) intact. I did not leave the TV on long enough to see if it would loop back on as some people experienced because each time I pushed the power button off.
At this point I did a bit more research on the net and read about cap problems on the Power Board... I checked mine and sure enough all 9, 3200 x 10V caps are bulging and two or three are also showing signs of leakage at the top.
My questions are... 1, do you think its just the caps that are responsible or is there likely to be a problem on the YSUS too?
and 2, is there a definitive way to find out, can the YSUS be checked out via fault finding (unplugging) or do I have to replace the caps first then see what happens?
I must point out that I have only a little experience with a soldering iron and despite my use of terms such as caps and YSUS, I only picked these terms up from reading over the last two days or so. Also I have no experience of removing caps but if necessary I will get an old pc board and practice until I feel confident but what concerns me is if the IC18 needs replacing on the YSUS then that currently seems to be a bigger challenge as it all looks a lot tighter spaced. Also, there are warnings on at least a couple of sites which suggest the IC18 is a bit of a b*gger to change out. I am considering purchasing a soldering station as this would seem to have more control than my current model. I do have a modest digital multimeter and can follow clear instructions.
I have searched for a replacement YSUS board but they seem to be in short supply apart from used ones which may also be on their way out (seems to be a common fault on Plasma TVs)
I have currently removed the main power board from the set so I can either repair it myself or send it off if needed. I suspect there is probably a little more fault finding to do first though?
Thanks for any help or suggestions which may be offered
Steviebilbo
It is probably worth mentioning that about 5 years ago (ish) it did suffer from sparkles (red) at the top and bottom of my TV and after having read about it on the net, I adjusted one of the two pots on the board BUT I used the picture quality as a basis for the setting NOT any voltage reading as that was not mentioned at the time. This may have resulted in the wrong voltage settings which in turn may have caused my current problem.
So, to my current problem ... from the top, I turned the TV on two days ago and the picture was distorted and flickering for about 15-20 seconds, I thought it was the broadband/cable signal so changed over channels and still had the same problem. About 5 seconds later the picture went off completely but the sound remained. There WAS NO POPPING sound or other symptom. I tried to bring up one of the menu pages but to no avail. I concluded that the picture generation function of the TV was broken.
I then spent about two hours on the net reading various similar stories before deciding to at least have a think/go at repairing it myself.
I removed the back of the set then checked the two T4 fuses on the YSUS - one had blown. I got a replacement 3.5 amp fuse (all I could get on a late Friday night) and installed it and tried again... The TV powered on (no picture though) and I noticed about 4 led indicators lit on the main board, about 2-3 seconds later there was an arcing type sound for a few seconds then a click (?relay?), the TV turned itself off and all but one of the led indicators dimmed until they were out completely. I turned the TV back on again and the same thing happened but without the arcing sound. The fuses are still (all) intact. I did not leave the TV on long enough to see if it would loop back on as some people experienced because each time I pushed the power button off.
At this point I did a bit more research on the net and read about cap problems on the Power Board... I checked mine and sure enough all 9, 3200 x 10V caps are bulging and two or three are also showing signs of leakage at the top.
My questions are... 1, do you think its just the caps that are responsible or is there likely to be a problem on the YSUS too?
and 2, is there a definitive way to find out, can the YSUS be checked out via fault finding (unplugging) or do I have to replace the caps first then see what happens?
I must point out that I have only a little experience with a soldering iron and despite my use of terms such as caps and YSUS, I only picked these terms up from reading over the last two days or so. Also I have no experience of removing caps but if necessary I will get an old pc board and practice until I feel confident but what concerns me is if the IC18 needs replacing on the YSUS then that currently seems to be a bigger challenge as it all looks a lot tighter spaced. Also, there are warnings on at least a couple of sites which suggest the IC18 is a bit of a b*gger to change out. I am considering purchasing a soldering station as this would seem to have more control than my current model. I do have a modest digital multimeter and can follow clear instructions.
I have searched for a replacement YSUS board but they seem to be in short supply apart from used ones which may also be on their way out (seems to be a common fault on Plasma TVs)
I have currently removed the main power board from the set so I can either repair it myself or send it off if needed. I suspect there is probably a little more fault finding to do first though?
Thanks for any help or suggestions which may be offered
Steviebilbo
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