Samsung LCD LA46B650T1R Display issues

[aviraj]

I had purchased the 46" Samsung LCD (Model - LA46B650T1R) in 2009. Recently the display started giving some issues and used to turn black (no picture, sound still working). This happened intermittently, now on start of the TV, the display is very dark and it is impossible to see anything.

One of the non-samsung technicians has diagnosed it as a logic board failure and says it is pretty common in samsung LCDs. From some of the samsung related forums I have read that samsung engineers usually recommend replacing the front panel and this costs around Rs. 25000 ($450) in addition to their service fees etc. I have also read that the problem might be as simple as replacing some capacitors.

My question: How can an LCD which is designed for almost 50000 hours of work, get major display issues in 3 yrs. I had read that similar failures were reported in USA for which Samsung got sued and finally agreed to a settlement. Is my issue similar to the one mentioned in the case? :\

 

[Harvey]

We have had several threads discussing the problem with failed capacitors in Samsung TV's and monitors. The first thing to do is open up the set and look at the electrolytic capacitors. They are the tall cylindrical components with a plastic sleeve and an aluminum top, possibly with a cross indentation. If the tops are domed like these, or if you see any signs of leakage around the base, they're bad.

You will need to know how to use a soldering iron to remove and replace them. It's a relatively easy job, but if you don't know how to do it, get help from someone who does. Replace them with new parts from a reputable manufacturer having these specs:

The same value and voltage rating (or higher).

The same temperature rating (rated at 105 deg. C).

Good high frequency rating.

The same mechanical size and lead spacing. Make sure that any cap that is taller or wider will fit in the available space.

Nichicon and Panasonic are two good brands. There are others. You can probably find them at Digikey or Mouser Electronics. The capacitor manufacturers should have links on their sites to help you find direct replacements with equal or better specs for the defective caps in the set.

Hope that helps.

 

[aviraj]

Thanks for the reply.
I had 2 technicians look at the issue. One was a local technician and other a samsung technician

Local technician said its a problem with the main board and will have to be replaced.

Samsung technician said its a problem with the board, but since the board is integrated with the display panel for this model, the entire panel needs to be replaced. This is significantly more expensive.

NOTE: In both cases the technicians did not even open the back cover of the TV so I'm guessing its a common problem

My questions:
1. Is the samsung technician right that the board (I dont know which one) is integrated with the display panel for this model and the entire display panel has to be replaced?
2. Can this be attributed to a manufacturing/design defect with this model
3. Read somewhere about main board and TCON board. I really dont know the difference between the two and which one in this case might be faulty.

 

[Harvey]

You're asking for more info than I have without a service manual for your set. Presumably, the Samsung tech had info on hand to confirm how the set is built, but some companies encourage their techs to steer you toward replacing the set, rather than repairing it.

You could ask the local tech if he checked the service manual before he gave you an answer or if he's sure it can be disassembled for repair. He may want to charge some minimum for the labor to check the set out and confirm the diagnosis and estimated cost of the repair. If so, many service techs will apply that minimum toward the final bill if you go ahead with the repair job.