NEC T-1000/ samsung s42sd-yd07

[superg]

These TV's aren't coming on. Client said they would not come on until after a long time.When I picked them up they were working. Opened up one and found no Vsus or Vg or Vs. Disconnecting the Y-main and Z-main results in no change. The LED8001 was flashing. Took out the power supply and found this substance on the bottom (trace side). Plan to scrub and re solder for cold solder joints.

[R_J]

Re: NEC T-1000/ samsung s42sd-yd07

That looks like water damage, I would check the other boards as well. cleaning might help but what I have found is traces can go open right near where the components are soldered due to corrosion. also I have found the ends of chip components (res. Cap.) can be completely eaten away.
Good luck.

[superg]

Re: NEC T-1000/ samsung s42sd-yd07

Update:- I used wd-40 to clean that stuff on the board then I resoldered the cold solder joints I could see and am still doing that. Borrowed a hair dryer and heated up the board (power supply) and when I turned on the TV it came on and worked. When I allowed it to cool down after turning off the fault returns. Standby light turn from red to blue but no raster. I purchased a can of air and used it to super cool the power supply after reheating with the hair dryer and to my amazement the tv comes on when I turn it on. Was hoping to isolate a section of the ps or a component. What am I missing? there is an LED on the power supply that's flashing 12 times which indicates a D12V error.

[superg]

Re: NEC T-1000/ samsung s42sd-yd07

Fixed. A fellow Tech lent me the following cap analyzer http://eds-inc.com/product/capanalyzer-88a-series-ii/ and I found 5 bad capacitors. Replaced them and viola, it works.