You might have replaced the capacitors, but did you checked the effeciency of the power supply?. That is; line to load regulation? Might not. This is the fault. For most flat panel power supplies are non repairable. It should be replaced as card basis.
http://electronicshelponline.blogspot.com/
Thank you for your answer. So you think its a power board problem and not a backlight rectifer problem then. And no i have not checked the effeciency of the power supply. How would i go about doing this. Is it just put a meter on the output of the board. Again thank you for your help.
Just load a filament type only [not CFL type or other] bulb, at its V+ output; and measure the voltage regulation. Just measure the B+ voltage, before connecting the bulb; and after connecting it. There can be a slight difference in voltage; at about 2.5VDC or so. Keep this condition for at least half an hour, and again check the voltage for any variation. There shouldn't be much. May +/_ 1V; but shouldn't be much more than that. Check the electrolytic capacitor connected across the B+ voltage [smoothing capacitor too]. I suggest to replace it. Check the main input DC voltage, and main smoothing capacitors. If any of these capacitors go DRY, the DC input voltage will be much lower; and so the output from the SMPS too. I'm ready to share my experience to anybody as far as I can. Wish you Good luck Nocolas. google.com/+GopakumarGopalan
×
SOURCE: "Upgrade" of Backlight Panel
just replace what failed.
I replace the surface mount FETs on the inverters.
SOURCE: Black screen on Zenith plasma tv's
Hello, My name is Dave and I can help you fix your Plasma TV. Give me a call. Feel free to give me a call @ 1-503-432-9904 or message me at [email protected]
Thank you!
Dave,
SOURCE: RE: Dell W4201C
i have a Dell W4201C ,the picture Dims or picture blinks when channel changes
SOURCE: Westinghouse 32 lcd tv - no picture no sound - set
Reset the tv and the cable or satalite boxes,replug it back an hour later let the tv reset it self back to factory setting and the boxes upgrade it software.The tv should work now.Not,than yes.It the Tuner main board.
Testimonial: "Quick response got me in the right area."
SOURCE: LT42HVi 42 in. LCD Worked fine
You need to check and see if the backlight inverter board is getting the 24vdc from the power supply.
Please learn more here:
Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague
Parts: www.shopjimmy.com
Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps.
Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series.
31 views
Usually answered in minutes!
×