How much is an average cost from a tv service tech to replace the power supply in a Samsung LCD LNT4661?

Sounds like The main power supply regulator section circuit fault. Either it will be a separate board, or the part of main board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/ It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.
Search the site by type in the "brand name" to your device; in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.
BN44-00341B - will be the number of power supply board used with this TV. Check it. If so, visit the site linked here to see its circuit diagram. Try to follow it, and do a repair work, or replace it.
Good luck

Your issue is your power supply. You can eather replace some capasitors on the power supply or you can replace the entire unit. If you open the LCD you should be able to see blow up capasitors.
Average repair is about $225 to $275 if they need to replace the entire board.

Thank you,

Hi,
There are two possibilities for back light off after 2 seconds.
One reason is back light inverter boards got defective for some reason (this tv has 2 back light inverter boards on either sides) and second possible cause is power supply is not giving out sufficient voltage supply to back light board.
Let me know your expertise level to provide you more technical info.
Thanks.

Try changing the bulb. They usually only have a life span of 40 000-60 000 hours of viewing before needing to be replaced

To all who are having power supply issues: Samsung is now acknowledging a problem with faulty capacitors. I called 1 800 726-7864 and they said they would repair certain out-of-warranty TVs if the problem is related to the capacitors. I just called and they are sending a service rep out to diagnose the problem

For a 50 inch plasma....its worth it, in my opinion y-boards cost around $149 to $189

the red light blinks due to a problem in the power supply or deflection circuit, this usually happens when one or two components start changing specified value or just entirely go out. Some samsung tvs do have replaceable boards but you still need to pinpoint the problem to a certain circuit board, either deflection or power board. It may be worth it to call a service tech and describe the problem to get a good idea on the repair cost.

I had the same problem - found the specific problem on forum boards. Fixed it myself for less than $20 with no electronics experience. Samsung installed bad capacitors...undervoltage for the LCDs from 2005-2007 (some models).  You can replace the capacitors yourself...go to http://www.tech-report.net/forums/viewtopic.php?f=37&t=67237  or  http://techreport.com/forums/viewtopic.php?f=37&t=62360  for instructions.  Good luck!

the tv has one part of the power supply working this is needed to have the microcontroller ready to work. But the tv needs more than that for work im talking 'bout the high voltage power supply who is now damaged. the parts required depends on the diagnosis in the bench but at least two are needed. the cost of this repair of course depends in how many parts are going to be replaced, but i concider this repair kind of average in this technology.

You may have a bad power supply. The worst case scenario is a defective panel. This power supply is very easy to change. Part number BN96-03057A
Average cost is $77.00

Best regards
circuitcity