My Samsung LN46c630 started flickering and having vertical lines on startup a while back so I cut the jumper on the power supply that is mentioned in several places on the internet and here.
This seemed to cure the flickering but the vertical lines still appeared but went away.
Eventually the TV started getting horizontal lines that came and went when on.
I took a look at it and discovered that 2 HDMI connectors were breaking away from the PCB (this is a pretty flimsy design, be careful with them in use!)
The fix for the HDMI connectors is to resolder the hold down posts from the bottom of the board with a fairly hot iron while pushing the connector toward the board from the top side. The hold down posts don't go thru the PCB but there is a via right below each of the 4 posts per connector, just flip the board over a couple times and you will see how they line up. There isn't a whole lot of danger of overheating the PCB just burning your finger so put the iron tip in the via, add a bit of solder and use your third hand to push on the connector as the solder sucks in, examine the joint before and after to see that the solder go to the post, give it a wiggle test to. Should become much more solid, I had to do the first one a couple times to get it right.
Put the unit back together and the lines were still there, if I tapped on the main PCB I could make them come and go or change. So I poked, prodded and gently pried on every component, with a plastic tool, on that PCB until I found that if I manipulated the 1" square chip w/the ceramic heatsink? directly above the RF connector I could reliably get the problems to occur.
This component appears to be of the Ball Grid Array type (Goggle it) but being that the ceramic piece was glued firmly to the top I couldn't get a number and look it up.
The assumption is that some of the connectors have broken their solder and this is why I could make the problem come and go as the leads touched and then didn't.
This is a fairly well documented failure with these devices and the correct repair is to remove the device, clean it, apply masked solder bearing paste and reheat it in a controlled fashion. The tool that does this appears to be in the $500 range on Ebay.
The happy hobbyist method involves applying “No Clean” liquid flux to the PCB next to the chip so it runs under it, masking around the chip with aluminum foil to protect the other parts, placing a thermal probe from a DMM (I used a Fluke 87v) on the chip surface and heating the chip with a high temperature heat gun (paint stripper) trying to adhere to a 4 minute process curve that I saw being used on a U-Tube video. The temp. was controlled by watching the temp. on the multimeter and having the kitchen timer counting down 4 minutes. I brought the temp. to about 225 Celsius trying to be cautious as you can overheat the chip and ruin it. At the end of about 3 mins. I started backing the heat gun away to ramp down the temp. This process has some technical flaws but when I reinstalled the board it worked as it should and I couldn't get the screen to show anything but what it is supposed to. It has been on for 12 hours now and is A-OK as of today Feb. 16, 2014, sometimes these repairs fail very early on after being fixed so time will tell. You should be able to try the repair again maybe raising the temp. a little or pre-heating the PCB to 100C from the bottom before running the heat profile, remember too much heat can ruin the chip!
The TV was manufactured in April of 2010. The TV started failing in early 2013 (lasted 3 years!!), the failures start off as odd artifacts showing up on the screen, sometimes colored lines, or colors are missing completely. Giving the TV a bit of a bump would restore the screen for a while but it got progressively worse.
Hope this helps someone, of course this repair applies to any ball grid array failure, I'm not sure how this might get made into a main instruction sticky but maybe that is the place for it as this method is used with some success on other products such as video cards. I repaired one of those last year in the oven and it is still working fine. There is a lot of info about these devices on the internet from manufacturers that supply heat curves and hobbyists trying other methods to fix them.
Bob
This seemed to cure the flickering but the vertical lines still appeared but went away.
Eventually the TV started getting horizontal lines that came and went when on.
I took a look at it and discovered that 2 HDMI connectors were breaking away from the PCB (this is a pretty flimsy design, be careful with them in use!)
The fix for the HDMI connectors is to resolder the hold down posts from the bottom of the board with a fairly hot iron while pushing the connector toward the board from the top side. The hold down posts don't go thru the PCB but there is a via right below each of the 4 posts per connector, just flip the board over a couple times and you will see how they line up. There isn't a whole lot of danger of overheating the PCB just burning your finger so put the iron tip in the via, add a bit of solder and use your third hand to push on the connector as the solder sucks in, examine the joint before and after to see that the solder go to the post, give it a wiggle test to. Should become much more solid, I had to do the first one a couple times to get it right.
Put the unit back together and the lines were still there, if I tapped on the main PCB I could make them come and go or change. So I poked, prodded and gently pried on every component, with a plastic tool, on that PCB until I found that if I manipulated the 1" square chip w/the ceramic heatsink? directly above the RF connector I could reliably get the problems to occur.
This component appears to be of the Ball Grid Array type (Goggle it) but being that the ceramic piece was glued firmly to the top I couldn't get a number and look it up.
The assumption is that some of the connectors have broken their solder and this is why I could make the problem come and go as the leads touched and then didn't.
This is a fairly well documented failure with these devices and the correct repair is to remove the device, clean it, apply masked solder bearing paste and reheat it in a controlled fashion. The tool that does this appears to be in the $500 range on Ebay.
The happy hobbyist method involves applying “No Clean” liquid flux to the PCB next to the chip so it runs under it, masking around the chip with aluminum foil to protect the other parts, placing a thermal probe from a DMM (I used a Fluke 87v) on the chip surface and heating the chip with a high temperature heat gun (paint stripper) trying to adhere to a 4 minute process curve that I saw being used on a U-Tube video. The temp. was controlled by watching the temp. on the multimeter and having the kitchen timer counting down 4 minutes. I brought the temp. to about 225 Celsius trying to be cautious as you can overheat the chip and ruin it. At the end of about 3 mins. I started backing the heat gun away to ramp down the temp. This process has some technical flaws but when I reinstalled the board it worked as it should and I couldn't get the screen to show anything but what it is supposed to. It has been on for 12 hours now and is A-OK as of today Feb. 16, 2014, sometimes these repairs fail very early on after being fixed so time will tell. You should be able to try the repair again maybe raising the temp. a little or pre-heating the PCB to 100C from the bottom before running the heat profile, remember too much heat can ruin the chip!
The TV was manufactured in April of 2010. The TV started failing in early 2013 (lasted 3 years!!), the failures start off as odd artifacts showing up on the screen, sometimes colored lines, or colors are missing completely. Giving the TV a bit of a bump would restore the screen for a while but it got progressively worse.
Hope this helps someone, of course this repair applies to any ball grid array failure, I'm not sure how this might get made into a main instruction sticky but maybe that is the place for it as this method is used with some success on other products such as video cards. I repaired one of those last year in the oven and it is still working fine. There is a lot of info about these devices on the internet from manufacturers that supply heat curves and hobbyists trying other methods to fix them.
Bob
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