Wednesday 12 January 2011

Samsung Syncmaster 540n no backlight.

A 15" LCD monitor to look at. Backlight would come on every time at power up for only two seconds then go off.

A few possibilities but a quick google pointed towards......thats right.... PSU capacitors. Id been here before with a Samsung LCD.

The PSU board was slightly different to the one that the google result gave but the culprit stood out for all to see with a bulge on top and a little brown stain. (fitting in nicely with my last post about observational repair !)



Once pulled from the board it measured at 90uf and falling instead of the specced 220uf. Replacement in it was time to check....


Result !

Conclusion, poor quality electrolitic capacitors strike again. (well, its my first blog post to cover them but it wont be the last Im sure).

I would comment the monitor came apart particularly easily, I liked the design.

1 comment:

  1. thanks, that's a nice info
    it helps me, I have 2 defect LCD, 1 is already normal.

    but i have 1 monitor, I already change the bulging caps (820uF and 330uF)
    but the problem still persist, it has no display. should I change the 1000uF, even if it's not bulge.
    and just for the info (now the LCD is buzzing, it is low enough but i can hear if the room is quiet)

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