itself as slow startup time and/or line patterns on the screen and/or sequence consisting of a relay click, followed by buzzing sound and unresponsive controls, followed by reboot.
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| Pretty line patterns |
At first, when it had been happening once every few months, the solution consisted of unplugging the tv from the outlet completely for 30 seconds. Usually that resolved the problem, and the tv resumed it's normal operation. I thought it was a fluke; however, when the tv started misbehaving more regularly, the feeling of annoyance finally crept in.
During a brief call to samsung technical support (1-800-samsung did it for me, make sure you have model, version and serial number from the side of the tv handy when you call), after the analyst verbally verified the model code, serial number and version, as well as the symptoms of the problem, she determined that it's most likely the capacitor issue on the power supply. Apparently, Samsung is aware of the the capacitor problem, and because it is so widespread, rather than initiating a mass recall, they address the concerns with the individual customers and dispatch technicians for a free capacitor repair (even if the tv is out of warranty). So i got my service order number, received the email confirmation with the assigned local Samsung repair facility. I got a call from the technician the next day, picked a day for the technician to come over and a 4-hour service window. The technician arrived bright and early in the morning the day after. He took of the back of the tv (there are 20+ screws that need to come off first). There were 4 capacitors in questions on the power supply (two 10-V and two 16-V capacitors); however they looked normal - there were no bulges or leaks. The technician did desolder the 4 capacitors from the power supply board and replaced them with 25-V equivalents anyway, just in case. The technician also advised that the issue may lay elsewhere as well since the original capacitors didn't exhibit the characteristics of failure. He suggested that for $95, he can troubleshoot the issue further and for little over $400 can replace the main board as well. I thanked him for that, refused the offer; and he was on his way, presumably to the next person to replace the capacitors. The whole process was very organized, streamlined and painless. I applaud Samsung for their technical support, not necessarily for the short lifespan of their products.
With that repair, the relay click and reboot has not happened any more. However, the slow startup time, the loud buzzing noise, the unresponsive controls and vertical lines persisted. The issue with power supply was seemingly resolved, however something else was not right. There was no way i would spend another $500 on this already expensive TV, when you can buy a brand new TV for almost the same amount these days...
So, i decided, my budget for this repair would be $150 at most. If i could not fix it for this amount - the tv would have been junked as my last Samsung product ever.
After searching the forums, i have to say, amateur tv repair is a very murky business. In forums, I found that the chassis for my model is GAM52MUS. With that, i was able to download a service manual from the usenet (don't ask me for links). The service manual has some pretty pictures and, most importantly, part number (part numbers are not pretty, they are just codes). Not being equipped with the wave generator or oscilloscope (i accept donations), i went the route of logic approximations and black box testing.
So... If it's not a power supply it could be either main board or t-conn board (whatever it is). I ruled out the t-conn board as an unlikely candidate, because according to the wiring diagrams, t-conn board is responsible for the picture alone, not the sound. When the controls locked and buzz was coming out of the speakers instead of the sound track from the source, the picture from the display source was normal. So, logically, that left the main board, part number BN94-01666E. According to various sources online BN94-01666P and BN94-01666A could be substituted, as a replacement parts as well. Even though internet never lies, I decided to go with the original part number. I searched for the lowest price, and found one for $93, including shipping from www.premiertvparts.com. Other prices ranged from $128 to $250. I happily ordered the part and waited... and then waited some more. Then called the vendor to ask about the status of my order. The published phone number was of course disconnected and nobody responded to the published email address. Feeling scammed, i rapidly emailed the vendor at their published email address sales@premiertvparts.com and requested to cancel my order with a full refund, since it has not been shipped yet. Even though i paid with PayPal account, i wanted to cover all basis in case there's a further dispute. I have not heard back from the vendor for 2 days. Then i got a canned email message from sales@premiertvparts.comand check on the order status. The status for the order "37" ( i guess not very many people order from that company and understandably so) gave me the tracking code for UPS. With that code i was able to check that premiertvparts.com submitted a pick-up order to UPS. Apparently, nobody reads email at Premier Tv Parts, so my cancel order request was completely ignored. It was only later, after searching the internet, i found that there are a lot of consumer complaints about Premier Electronics (as they are also known). Upset at myself for my poor judgement, i, nevertheless, decided to wait and see what kind of monster would spring at me from the package. The beaten up box (thanks UPS ground shipping) arrived 7 days later.
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| UPS piñata |
Inside that box was yet another box... no, just kidding - no more boxes - instead there a poorly packaged main board for Samsung tv
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| something that looks like a used samsung main board. {notice, i have aspirin ready in the corner of the picture} |
with the part number BN94-01666E, and a serial number ...scratched off. Stolen? Maybe. I won't speculate further. At least the part number was right. Knowing that i am dealing with a company of questionable reputation and presuming that returning the component would be more hassle that it's worth, i decided to try my luck and install it.
I placed the 52" sammy on a mat with the display facing down. Grabbed my Phillips (you only need 1 screwdriver for the whole job) and removed 4 screws from the bottom center to disconnect the stand. Then I removed 4 vesa mount screws, 15 cover screws and, finally, lifted the cover.
The main board is in the lower right hand corner (where all the connectors live)
I removed 6 screws from the Scaler Board shield case, removed 2 vga cable adaptors, disconnected the cables from the main board, removed 6 screws holding the the main board to the frame, lifted the main board and pried the case adapter from the main board.
When comparing the original board and the "new" board, they seemed identical, except for the scratched off serial number. So it was a good sign, relatively speaking. At this point, i substituted the main board, and put everything together, reversing the order of steps from the disassembly. Plugged the HDMI cables for the sources (DirecTV and PS3) back into HDMI1 and HDMI2 ports. Plugged in the power and ...it's alive. After 2 days of operation, there have not been any artifacts or recurring symptoms. The only difference is that the board came with firmware version 2008.9 with a build date of 20080915. The latest available firmware for download from samsung is 2007.0 with a build date of 20080905. I confirmed with Samsung Tech support (via chat) that 2008.9 is the latest version and that it's not available for download. So if i decide to downgrade it to 2007.0 to get clearer picture, i might loose the ability to go back to 2008.9. Still pondering on that silly concept...
In the meantime, say hello to an amateur tv repairman - moi. :) It wasn't as bad as i thought it would be. Besides, at $93 total cost, i came way under my budget and way way below $495+ that a tv repair shop would have charged me. Replacing power supply or t-conn board would probably require the same amount of effort. Just watch out for LVDS cable (that thing doesn't look very sturdy).
I was overwhelmed by the amount of screws on the tv case (almost 40 screws); however, i was armed with a pdf of a service manual, a single Phillips screwdriver and a motivation to save money.
For this particular project, i'd say the difficulty of repair is 3/10.
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