LG 60PK950 - multiple issues, chain of events
Hi All,
I have the TV mentioned in the subject.
Couple of months ago, it started to show green vertical lines, appearing in the same positions. There were only one or two at the beginning, then it started to grow to around the amount of 10. All of them were in the middle third segment.
Then recently, we decided to paint the living room, so I removed the TV from the mount and disassembled it. Before doing this, I downloaded some materials about the connections, panels, troubleshooting of this specific model family (60PK<x>) to get aligned in the topic.
Let me drive you through the steps of troubleshooting and getting deeper in the mud:
1. Center X-Board (EBR63451301) and Control Board (EBR63450301) connection cleaning and reseating.
2. Turning the TV on: for couple of minutes the mentioned green lines were still spotted at the same locations, then a sudden, silent pop from somewhere around between the mid and top section of the TV. Result: no middle third vertical part = pitch black. Swearing...
3. Some more troubleshooting guide I downloaded. Reading, learning. Got to the conclusion that either the center X-Board or the Control Board went out.
I connected the P104 tape connector to P102 to check if the center controller would do anything to the right X-Board and I saw some white garbage on the screen. This is why I supposed that it might not be the Control Board that was faulty, but the center X-Board, as it feeds something from P102 at least.
4. I found a center X-Board on ebay, so I took my chance. Couple of weeks of waiting, happiness after receiving the package, then very sad face when I realized that it had not helped at all.
5. More troubleshooting with multi-meter. X-Board voltages are fine (both 60V coming from the Y-SUS (P114 connector -> P220 -> P320) and 3.3V RGB signals coming from the Control Board (P102 -> P210).
6. Then I decided to check the Control Board, as that was indicated in the troubleshooting documentation as a second possible candidate. I removed the LVDS cable and tried the test mode by shorting the AUTO GEN pins. Same issue, but the test mode was working properly. Control Board voltages, resistance seemed also to be fine, 3.3V, 5.1V etc. Whatever should have been measured were fine, even the P102 and P210 pins had the 3.3V. Green LED properly producing an irregular, but firm blinking. Then, I did a big mistake, I don't know for sure what the mistake was, but I changed the meter to Hz mode to check the oscillator whether it was really 25MHz or not. This move turned the TV off after hearing a similar, not so loud popping sound from the top-right section of the TV.
7. After some search, I figured out that the FS103 fuse (6.3A/250V) - protecting the VS line - got broken on the Z-SUS Board (EBR63450501). Hair pulling. Bigger buzzing noise from the SMPS while the TV was turned on and low intensity issue was observed. BTW, before this, I got some measurements on this board, and seemed like to be fine. 104.9V was measured on VZB after 2 minutes heating (was 99V at initial switch on), I think it was fine, as has to be 105V. I successfully ruined it.
8. I put in a new fuse, hoping for that only the fuse got bad and only due to the oscillator measurement. No success, could not get back to at least the original middle vertical black bar symptom. The TV switches off after hearing the first relay click, going back to stand-by.
9. If I remove the P102 connector (SMPS->Z-SUS power connector), then the TV turns on and has the left/right thirds working (still middle black bar issue), but of course the intensity is very low, the picture can be hardly seen.
Voltages are fine on P811 (SMPS).
---------------------
This is where I am now.
Questions:
Can I assume that the SMPS is still working properly (right measurements on P102) and I have now issue with at least the Z-SUS board (EBR63450501)?
What would you check on the Z-SUS? Visually it looks good, no popped/leaking capacitors, no other issues.
If I could manage to repair/replace the Z-SUS, expecting that it is the culprit now, what could be causing the middle third black vertical bar?
I have the TV mentioned in the subject.
Couple of months ago, it started to show green vertical lines, appearing in the same positions. There were only one or two at the beginning, then it started to grow to around the amount of 10. All of them were in the middle third segment.
Then recently, we decided to paint the living room, so I removed the TV from the mount and disassembled it. Before doing this, I downloaded some materials about the connections, panels, troubleshooting of this specific model family (60PK<x>) to get aligned in the topic.
Let me drive you through the steps of troubleshooting and getting deeper in the mud:
1. Center X-Board (EBR63451301) and Control Board (EBR63450301) connection cleaning and reseating.
2. Turning the TV on: for couple of minutes the mentioned green lines were still spotted at the same locations, then a sudden, silent pop from somewhere around between the mid and top section of the TV. Result: no middle third vertical part = pitch black. Swearing...
3. Some more troubleshooting guide I downloaded. Reading, learning. Got to the conclusion that either the center X-Board or the Control Board went out.
I connected the P104 tape connector to P102 to check if the center controller would do anything to the right X-Board and I saw some white garbage on the screen. This is why I supposed that it might not be the Control Board that was faulty, but the center X-Board, as it feeds something from P102 at least.
4. I found a center X-Board on ebay, so I took my chance. Couple of weeks of waiting, happiness after receiving the package, then very sad face when I realized that it had not helped at all.
5. More troubleshooting with multi-meter. X-Board voltages are fine (both 60V coming from the Y-SUS (P114 connector -> P220 -> P320) and 3.3V RGB signals coming from the Control Board (P102 -> P210).
6. Then I decided to check the Control Board, as that was indicated in the troubleshooting documentation as a second possible candidate. I removed the LVDS cable and tried the test mode by shorting the AUTO GEN pins. Same issue, but the test mode was working properly. Control Board voltages, resistance seemed also to be fine, 3.3V, 5.1V etc. Whatever should have been measured were fine, even the P102 and P210 pins had the 3.3V. Green LED properly producing an irregular, but firm blinking. Then, I did a big mistake, I don't know for sure what the mistake was, but I changed the meter to Hz mode to check the oscillator whether it was really 25MHz or not. This move turned the TV off after hearing a similar, not so loud popping sound from the top-right section of the TV.
7. After some search, I figured out that the FS103 fuse (6.3A/250V) - protecting the VS line - got broken on the Z-SUS Board (EBR63450501). Hair pulling. Bigger buzzing noise from the SMPS while the TV was turned on and low intensity issue was observed. BTW, before this, I got some measurements on this board, and seemed like to be fine. 104.9V was measured on VZB after 2 minutes heating (was 99V at initial switch on), I think it was fine, as has to be 105V. I successfully ruined it.
8. I put in a new fuse, hoping for that only the fuse got bad and only due to the oscillator measurement. No success, could not get back to at least the original middle vertical black bar symptom. The TV switches off after hearing the first relay click, going back to stand-by.
9. If I remove the P102 connector (SMPS->Z-SUS power connector), then the TV turns on and has the left/right thirds working (still middle black bar issue), but of course the intensity is very low, the picture can be hardly seen.
Voltages are fine on P811 (SMPS).
---------------------
This is where I am now.
Questions:
Can I assume that the SMPS is still working properly (right measurements on P102) and I have now issue with at least the Z-SUS board (EBR63450501)?
What would you check on the Z-SUS? Visually it looks good, no popped/leaking capacitors, no other issues.
If I could manage to repair/replace the Z-SUS, expecting that it is the culprit now, what could be causing the middle third black vertical bar?
Comment