Ok, guys, got mine done as well. Thanks to all for the pics, info, answers, etc.. Was about to haul this to a sevice shop before I found this.
I replaced the board in about an hour and did not have to do any convergence adjustments. I did run perfect focus anyway, but did not have too, it worked immediately.
Congrats! Good thing you did not do what a lot of people do. Most try to do an alignment on the convergence in the service mode. then it can take hours trying to get it set up again.
Hello all. Very helpful thread, although it is a lot to take in. Hopefully someone can help us with a fix. Also, thanks for posting the service manual. My husband was about to buy one from Samsung....
We, too, appear to have convergence problems on my Samsung HCL4715W. About a week ago the picture became very distorted, with red lines looking most distorted. In trying to perfect focus, the blue and green aligned just fine, but the red would not budge. In addition, we are seeing the "pin cushion" effect at the top and bottom of the screen, similar to what is described in this thread.
Hoping for a quick and easy fix, we ordered a new convergence board (part number AA95-01799G), but it did not fix the problem. Luckily, it can be returned.
As we understand it, we most likely need to replace the convergence ICs on the subboard. While my husband is good with electronics, he is wary of having to solder anything this delicate. Can we just replace the entire subboard with a new one? If so, how does that affect the project? Lastly, since quality of parts seems to be an issue, where do you all recommend getting the parts from?
Many thanks.... I had to ask on his behalf because my husband hates asking for help!!!!
Yes that board is order a lot by the do it yourselfer techs. Although you are a lucky one if you can return it, as most places do not allow this. The board you ordered is called the digital convergence board. This board hardly ever goes bad. I have had to replace this board only once. The board you need is called the power/convergence board and is available here http://www.samsungparts.com/part_detail.asp?catalog%5Fname=Parts+and+Acc...
Or you can take this part number and get it somewhere else if you like, You could also contact ptscorp.com and find out how much it is for a rebuilt board or they can rebuild your board. Good Luck
Thanks, Larry. That helps. I contacted an online place about repairing the ICs (STK392-040) on our existing board, along with any necessary resistors and fuses, and he quoted me $160 inluding shipping. Am I missing something or does it make sense to just buy a new board? I want to make sure these are not two different solutions I am thinking about. Assuming we just buy a new board, I think my husband can install it since he was able to remove the existing one.... but let me know if that is flawed reasoning. He is good with electronics, but doesn't have 10 hours to spend on this. Thanks again!
No your not missing anyhing at all and getting a new board should take less then 2 hours at most to replace as long as you or your hubby did not attempt to adjust the convergence in the service mode before you replaced the board.
Larry Dillon said: Bass, the photobucket wants a password man.
Larry, I read this thread about the convergence problem and the red allignment going out. It was very informative and matched my problem so I ordered the replacement part, AA95-01846D, for my Samsung HCL4715W TV. Spent the afternoon replacing the board and now the color looks great!
Only one problem left - no audio. I had audio before I replaced the board, now it is mute. I have double-checked for a loose connection and can not find anything loose or any mis-alligned connections. My initial guess is the new AA95-01846D is the problem, but from what I can tell in the schematics, the audio does not go to this board.
Do you have any thoughts or ideas as to what could be the problem?
I did. I checked other audio settings / setup as well. I can get sound from my cable box into the stereo, so I know there is a good audio being received. But it is not coming out of the TV.
You are going to have to go over EVERY connector in the set and make sure it is seated correctly and make sure the plug is inserted completely and not half way out. I have seen this a thousand times if not more with seasoned techs. It is time consuming but is always the problem when there is one problem and then after it is repaired there is another issue with the set. YOU HAVE TO GO TO EACH AND EVERY CONNECTION BY HAND AND FEEL IT, NOT BY SIGHT.
Larry, Thanks. Was hoping you would know which connector is likely to be the culprit. I did check by inspecting each connector and pushing each to make sure it was seated. Now I'll go back and disconnect & reconnect each next to see if that takes care of it.
Larry thanks for all of your guidance a couple of weeks ago. We went ahead and bought a new TV and my husband hasn't gotten around to replacing the board yet. Hopefully he will in the next week or so and I will post an update and hopefully won't need any more help! Thanks again!
Larry, I found the problem with the audio. On the main board (on left when viewed from rear), there is a small connector on the upper-left area of the board. It has a small ribbon cable and when I pulled the tray out to remove the AA95-01846D (center board), the connection came loose. It was hard to find as the connection is hidden and the cable did not stray far when it disconnected. I think it is CN901, but it could be CN602. So the problem was not with the new AA95-01846D and was on the main board.
Thank you and everyone else that contributed to this thread. This saved me several hundred dollars in a service call, and potentially a couple thousand for a replacement TV.
Great news man!I really did not think you had a bad convergence board. It is ALWAYS a connector or plug connection when you fix one problem and get another in a set.
I have the HCL 4715 Samsung too - read all the blogs - started to order - Sears called and said they were almost here after i had cancelled - so i thought why not see what they say is wrong? so they changed the convergence board (had the red problem bad) resistors burnt etc. - - he changed the board and it was running hot as blue blazes and he said the DCU was bad and causing the ICs to blow. Sound right? He took his new board out fast as he said it was going to ruin the new board. whatcha' think about that?
Where does the service manual explain how to take the board out? Do I just have to follow the diagram?
My question is, how do you take off the input piece. I'm guessing it's the part in the manual that I have a blue line going to. Then I have a red line going to what I'm assuming should slide out so you can get to the boards?
Larry, thanks so much for all of your guidance. My husband FINALLY replaced the power/convergence board on our set and it works! Yay! It took him less than an hour, but he is fairly good with electronics, although by no means an expert. Now if I could just figure out what to do with two bg TVs since we bought a new LCD TV when it first broke.....
I've had this HDTV for 6 years, two moves, no problems until now. It began shutting itself off intermittently about a week ago, and last night it did not come up at all. Front panel power button does nothing, remote control blinks TIMER LED once for each keystroke, but does not come on. No sound of relay clicking or power supplies coming on.
Thanks to TechLore's resource page I downloaded the service manual and printed schematics. Power supply board seems to work fine: I took it out, applied power, and measured good voltages at all outputs. (To do this you need to jumper the two LINE signals going to the "SUB" (high voltage) board since the SUB board connects them with a relay. Be careful, these are 120VAC.)
SUB board generates 5V STD (standby) voltage fine. I checked the SUB board power relay and it clicks on and off fine. (I did this with power off, using a 9V battery to provide power to the 5V STD regulator on the SUB board.)
So the next likely culprit is the "MICOM" (Z-80) controller board, which turns on the power relay. It's either bad or getting bad information from somewhere... but where?
Has anyone seen similar behavior and/or have suggestions?
koolzero said: Can someone post a picture of the pico fuse and a picture of where it's located?
On my HCL4715W POWER board they look like white 1/2W resistors. They're hidden deep within the forest of tall heat sinks near connectors CN802 and CN803, and are labeled FD805S, FD806S, FD871S, and FD854S. I actually took my POWER board out to test it, which makes it much easier to see them -- and replace any that need replacing.
it is in over load protection it sounds like. Disconnect the convergence board with the large STK driver iC's and see if the set will switch on. If it does replace the IC's on the board. if you replace the board, the convergence alighnment gets very complicated. Good Luck
Thank you for the quick reply. I tried disconnecting the convergence board, but no change in behavior (power relay did not click on).
Investigating further, I found that the PROTECT signal on the SUB board was high even though only standby STD-5V was on. This signal is normally triggered by excessive high voltage which could zap the user with X-rays, and causes the MICOM (control CPU) to turn the set off. In this case PROTECT was not being pulled high by the high voltage circuitry since the main power supply wasn't on. It turned out there was a drop of <b>black oily goo</b> on the MICOM board which was weakly shorting PROTECT to STD-5V. I cleaned off the goo and PROTECT is no longer pulled high.
Unfortunately, the TV still won't power up. Service Manual section 4-4-6 (Fail Safe Circuit Check) says that if the TV shuts itself off due to excessive high voltage it's necessary to "reset it after about 30 seconds". Is there some special key combination needed to "reset" the TV?
I got lucky! It turns out my problem (HCL4715W does not power on) was entirely related to oil in the MICOM (control CPU) card. I looked carefully at the board under a bright light and saw that the black oily goo was under the 64-pin Euro connector as well. I tilted the connector (desoldered one of the hold-down clips) and cleaned under it with isopropyl alcohol, and also around the pins that were in the oily area. This actually changed the resistance between pins so the oil was definitely acting as a weak short. I let everything dry, plugged MICOM in and TV came right up.
Larry, I've seen a few of your comments about oil leaking from picture tubes and messing things up. Do you have a longer article describing the oil in more detail, e.g., why it's used, what it does to PC boards (and humans), and how best to clean it up and prevent future problems?
Larry, everything has been going good since replacing the convergence board about a month ago, until today. Now i have a pink tint to everything all of a sudden. I dont know if this is related to the board or not, I was thinking it may be a gun issue or something. Do you know what would cause this, and what I could do to check/fix it? Thanks
If the set is a little pink, the red tube is set a little too high on the gain. go into the service menu and lower the red slightly, and dont forget to write down the numbers before yo change them incase you make a mistake!
it comes from a leaky gasket on one of the picture tubes. It is used as a coolant for the picture tubes. It is not great environment but I am not sure about humans.
Thanks larry, I will try that out. I would say its more than a little pink. It is a light pink, but the whole screen is somewhat pink, not just some of it. Watching a show last night there was a lake, the water was light pink, as an example.
thanks Larry, going to try this out tonight. I have never used service mode, so just curious, when I do this, how do I know when its "right" so that I have the best picture? Or do I just have to do it until it looks right to me? I shouldnt run the auto focus or anything like that should I? Thanks
Ok, guys, got mine done as well. Thanks to all for the pics, info, answers, etc.. Was about to haul this to a sevice shop before I found this.
I replaced the board in about an hour and did not have to do any convergence adjustments. I did run perfect focus anyway, but did not have too, it worked immediately.
Congrats! Good thing you did not do what a lot of people do. Most try to do an alignment on the convergence in the service mode. then it can take hours trying to get it set up again.
Hello all. Very helpful thread, although it is a lot to take in. Hopefully someone can help us with a fix. Also, thanks for posting the service manual. My husband was about to buy one from Samsung....
We, too, appear to have convergence problems on my Samsung HCL4715W. About a week ago the picture became very distorted, with red lines looking most distorted. In trying to perfect focus, the blue and green aligned just fine, but the red would not budge. In addition, we are seeing the "pin cushion" effect at the top and bottom of the screen, similar to what is described in this thread.
Hoping for a quick and easy fix, we ordered a new convergence board (part number AA95-01799G), but it did not fix the problem. Luckily, it can be returned.
As we understand it, we most likely need to replace the convergence ICs on the subboard. While my husband is good with electronics, he is wary of having to solder anything this delicate. Can we just replace the entire subboard with a new one? If so, how does that affect the project? Lastly, since quality of parts seems to be an issue, where do you all recommend getting the parts from?
Many thanks.... I had to ask on his behalf because my husband hates asking for help!!!!
Yes that board is order a lot by the do it yourselfer techs. Although you are a lucky one if you can return it, as most places do not allow this. The board you ordered is called the digital convergence board. This board hardly ever goes bad. I have had to replace this board only once. The board you need is called the power/convergence board and is available here http://www.samsungparts.com/part_detail.asp?catalog%5Fname=Parts+and+Acc...
Or you can take this part number and get it somewhere else if you like, You could also contact ptscorp.com and find out how much it is for a rebuilt board or they can rebuild your board. Good Luck
Thanks, Larry. That helps. I contacted an online place about repairing the ICs (STK392-040) on our existing board, along with any necessary resistors and fuses, and he quoted me $160 inluding shipping. Am I missing something or does it make sense to just buy a new board? I want to make sure these are not two different solutions I am thinking about. Assuming we just buy a new board, I think my husband can install it since he was able to remove the existing one.... but let me know if that is flawed reasoning. He is good with electronics, but doesn't have 10 hours to spend on this. Thanks again!
No your not missing anyhing at all and getting a new board should take less then 2 hours at most to replace as long as you or your hubby did not attempt to adjust the convergence in the service mode before you replaced the board.
Larry, I read this thread about the convergence problem and the red allignment going out. It was very informative and matched my problem so I ordered the replacement part, AA95-01846D, for my Samsung HCL4715W TV. Spent the afternoon replacing the board and now the color looks great!
Only one problem left - no audio. I had audio before I replaced the board, now it is mute. I have double-checked for a loose connection and can not find anything loose or any mis-alligned connections. My initial guess is the new AA95-01846D is the problem, but from what I can tell in the schematics, the audio does not go to this board.
Do you have any thoughts or ideas as to what could be the problem?
I did. I checked other audio settings / setup as well. I can get sound from my cable box into the stereo, so I know there is a good audio being received. But it is not coming out of the TV.
You are going to have to go over EVERY connector in the set and make sure it is seated correctly and make sure the plug is inserted completely and not half way out. I have seen this a thousand times if not more with seasoned techs. It is time consuming but is always the problem when there is one problem and then after it is repaired there is another issue with the set. YOU HAVE TO GO TO EACH AND EVERY CONNECTION BY HAND AND FEEL IT, NOT BY SIGHT.
Larry, Thanks. Was hoping you would know which connector is likely to be the culprit. I did check by inspecting each connector and pushing each to make sure it was seated. Now I'll go back and disconnect & reconnect each next to see if that takes care of it.
Oh I could research and name several, but it would be a major waiste of time. You need to do as I said or pay a tech to trouleshoot what you did.
Larry thanks for all of your guidance a couple of weeks ago. We went ahead and bought a new TV and my husband hasn't gotten around to replacing the board yet. Hopefully he will in the next week or so and I will post an update and hopefully won't need any more help! Thanks again!
Larry, I found the problem with the audio. On the main board (on left when viewed from rear), there is a small connector on the upper-left area of the board. It has a small ribbon cable and when I pulled the tray out to remove the AA95-01846D (center board), the connection came loose. It was hard to find as the connection is hidden and the cable did not stray far when it disconnected. I think it is CN901, but it could be CN602. So the problem was not with the new AA95-01846D and was on the main board.
Thank you and everyone else that contributed to this thread. This saved me several hundred dollars in a service call, and potentially a couple thousand for a replacement TV.
Great news man!I really did not think you had a bad convergence board. It is ALWAYS a connector or plug connection when you fix one problem and get another in a set.
I have the HCL 4715 Samsung too - read all the blogs - started to order - Sears called and said they were almost here after i had cancelled - so i thought why not see what they say is wrong? so they changed the convergence board (had the red problem bad) resistors burnt etc. - - he changed the board and it was running hot as blue blazes and he said the DCU was bad and causing the ICs to blow. Sound right? He took his new board out fast as he said it was going to ruin the new board. whatcha' think about that?
Can someone post a picture of the pico fuse and a picture of where it's located?
sounds about right. Hard to say without testing a few things first, but I am sure he has had this experience before.
Where does the service manual explain how to take the board out? Do I just have to follow the diagram?
My question is, how do you take off the input piece. I'm guessing it's the part in the manual that I have a blue line going to. Then I have a red line going to what I'm assuming should slide out so you can get to the boards?
Larry, thanks so much for all of your guidance. My husband FINALLY replaced the power/convergence board on our set and it works! Yay! It took him less than an hour, but he is fairly good with electronics, although by no means an expert. Now if I could just figure out what to do with two bg TVs since we bought a new LCD TV when it first broke.....
Thanks again for your help!!!
Samsung HCL4715W does not power on.
I've had this HDTV for 6 years, two moves, no problems until now. It began shutting itself off intermittently about a week ago, and last night it did not come up at all. Front panel power button does nothing, remote control blinks TIMER LED once for each keystroke, but does not come on. No sound of relay clicking or power supplies coming on.
Thanks to TechLore's resource page I downloaded the service manual and printed schematics. Power supply board seems to work fine: I took it out, applied power, and measured good voltages at all outputs. (To do this you need to jumper the two LINE signals going to the "SUB" (high voltage) board since the SUB board connects them with a relay. Be careful, these are 120VAC.)
SUB board generates 5V STD (standby) voltage fine. I checked the SUB board power relay and it clicks on and off fine. (I did this with power off, using a 9V battery to provide power to the 5V STD regulator on the SUB board.)
So the next likely culprit is the "MICOM" (Z-80) controller board, which turns on the power relay. It's either bad or getting bad information from somewhere... but where?
Has anyone seen similar behavior and/or have suggestions?
Thanks!
On my HCL4715W POWER board they look like white 1/2W resistors. They're hidden deep within the forest of tall heat sinks near connectors CN802 and CN803, and are labeled FD805S, FD806S, FD871S, and FD854S. I actually took my POWER board out to test it, which makes it much easier to see them -- and replace any that need replacing.
it is in over load protection it sounds like. Disconnect the convergence board with the large STK driver iC's and see if the set will switch on. If it does replace the IC's on the board. if you replace the board, the convergence alighnment gets very complicated. Good Luck
Thank you for the quick reply. I tried disconnecting the convergence board, but no change in behavior (power relay did not click on).
Investigating further, I found that the PROTECT signal on the SUB board was high even though only standby STD-5V was on. This signal is normally triggered by excessive high voltage which could zap the user with X-rays, and causes the MICOM (control CPU) to turn the set off. In this case PROTECT was not being pulled high by the high voltage circuitry since the main power supply wasn't on. It turned out there was a drop of <b>black oily goo</b> on the MICOM board which was weakly shorting PROTECT to STD-5V. I cleaned off the goo and PROTECT is no longer pulled high.
Unfortunately, the TV still won't power up. Service Manual section 4-4-6 (Fail Safe Circuit Check) says that if the TV shuts itself off due to excessive high voltage it's necessary to "reset it after about 30 seconds". Is there some special key combination needed to "reset" the TV?
Thank you again for your help.
I got lucky! It turns out my problem (HCL4715W does not power on) was entirely related to oil in the MICOM (control CPU) card. I looked carefully at the board under a bright light and saw that the black oily goo was under the 64-pin Euro connector as well. I tilted the connector (desoldered one of the hold-down clips) and cleaned under it with isopropyl alcohol, and also around the pins that were in the oily area. This actually changed the resistance between pins so the oil was definitely acting as a weak short. I let everything dry, plugged MICOM in and TV came right up.
Larry, I've seen a few of your comments about oil leaking from picture tubes and messing things up. Do you have a longer article describing the oil in more detail, e.g., why it's used, what it does to PC boards (and humans), and how best to clean it up and prevent future problems?
Thanks. This is a great site.
Larry, everything has been going good since replacing the convergence board about a month ago, until today. Now i have a pink tint to everything all of a sudden. I dont know if this is related to the board or not, I was thinking it may be a gun issue or something. Do you know what would cause this, and what I could do to check/fix it? Thanks
If the set is a little pink, the red tube is set a little too high on the gain. go into the service menu and lower the red slightly, and dont forget to write down the numbers before yo change them incase you make a mistake!
it comes from a leaky gasket on one of the picture tubes. It is used as a coolant for the picture tubes. It is not great environment but I am not sure about humans.
Thanks larry, I will try that out. I would say its more than a little pink. It is a light pink, but the whole screen is somewhat pink, not just some of it. Watching a show last night there was a lake, the water was light pink, as an example.
still sounds like the red needs to be lowered a notch or two.
thanks Larry, going to try this out tonight. I have never used service mode, so just curious, when I do this, how do I know when its "right" so that I have the best picture? Or do I just have to do it until it looks right to me? I shouldnt run the auto focus or anything like that should I? Thanks
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