Just out of warranty at one year old, this started out intermittently then got progressively worse, now it takes many cycles for it to work if at all before giving up ;-)
Turn the TV on and it makes the Samsung powerup noise, backlighting comes on but nothing on the screen. After about 15 seconds, it will cycle through the powerup again and keep cycling until it eventually comes on. When it is cycling you can't turn it off to stop this, it has to be unplugged. Plugging it back in results in the same cycling until it finally comes on or until you unplug it. Once on, the TV will work fine for hours till turned off.
No swelled caps or cold solder joints on the PS board, unplug the main board and the backlighting comes on and all voltages seem to be normal and stable at 5.25V and 13.05V, have not load tested them yet. Cursory inspection of the main board under magnification shows no obvious flaws or solder problems.
When the TV finally comes on and you shut it down, the 5V standby voltage is present and stable. Tried unplugging the power button as well as the TCON cable with no change.
The two PS test points indicated in pic read 13V during cycling, the one marked 13V (EY80) goes to 0V when cycling, then back up, but the one marked 15V (EY76) cycles up to 15V and back. With main board unplugged EY80 stays at 13V and EY76 measures 15.4V.
PS BNN44-00666A
Main BN94-07695D
I have basic electronics skills, Fluke meter, good soldering skills, temp controlled iron but no hot air station.
Any help is greatly appreciated.
Turn the TV on and it makes the Samsung powerup noise, backlighting comes on but nothing on the screen. After about 15 seconds, it will cycle through the powerup again and keep cycling until it eventually comes on. When it is cycling you can't turn it off to stop this, it has to be unplugged. Plugging it back in results in the same cycling until it finally comes on or until you unplug it. Once on, the TV will work fine for hours till turned off.
No swelled caps or cold solder joints on the PS board, unplug the main board and the backlighting comes on and all voltages seem to be normal and stable at 5.25V and 13.05V, have not load tested them yet. Cursory inspection of the main board under magnification shows no obvious flaws or solder problems.
When the TV finally comes on and you shut it down, the 5V standby voltage is present and stable. Tried unplugging the power button as well as the TCON cable with no change.
The two PS test points indicated in pic read 13V during cycling, the one marked 13V (EY80) goes to 0V when cycling, then back up, but the one marked 15V (EY76) cycles up to 15V and back. With main board unplugged EY80 stays at 13V and EY76 measures 15.4V.
PS BNN44-00666A
Main BN94-07695D
I have basic electronics skills, Fluke meter, good soldering skills, temp controlled iron but no hot air station.
Any help is greatly appreciated.
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