# 32" LCD TV SAMSUNG LE32S73BD monitor doesn't turn on, blinking power led.



## rodion15 (Oct 26, 2011)

Hi: I have an 32" LCD TV SAMSUNG LE32S73BD that doesn't turn on. The red power led on the front gets blinking when you try to turn it on (about 0,5 seconds per blink). I've opened it and measured voltages in output of the Power Suppy board (BN96-03775A), on the CNM801 connector that connects power supply and main board, using a digital multimeter: 
5v output: I get instead 2.1 to 0.7v, intermittent, changing every 0.5 seconds just like the Power Led.
12v output: 3.5v to 1.8v, intermittent, changing every 0.5 seconds just like the Power Led.
So I guess this board is bad. I see no bulged electrolitic capacitors. The fuse is OK. Am I right?. This is the first time I'm trying to repair a monitor although I've repaired other stuff before.
My doubts: 
- how can I be sure some other board such as the main board isn't affecting the output and thus the power supply board is OK?. If I remove the ribbon connector on the main board, I get no output voltages, so I don't see how I can test the power supply board isolated.
- I'd welcome any info as to the function of the parts in this power supply board, It seems sheet 1of2 in the schematic diagram is dedicated to power factor correction, right?

By the way: if you can advice some LCD monitor repair courses/books/learning websites and also forums, I'd be grateful. (I'm reading Jestine Yong "LCD Monitor repair" but I need much more).

Thanks a lot.


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## namaste09 (Jan 26, 2014)

Definitely Power Supply issue if the 12v is fluctuating. However, disconnect the connector from the Power Supply to the main. Check the voltage on the stby. if steady then Main is defective.


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