Mulja tv repair portal
Equipment Repairs => LCD TV forum => Topic started by: Turnip on September 28, 2011,12:57:02
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Hi folks,
Had my first 17IPS10-3 and 17MB25-3 set in today. Backlight comes on, then after 2 seconds blue LED lights up on LVDS then backlight goes out followed by blue LVDS led.
Note that there is but one inverter tranny and it reads the same on both secondaries.
Secondary caps look good and diodes check OK.
Any thoughts ? - Thanks - Chris
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hi chris dont think im stupid but in the menu check for an active backlight control if its there switch it off had the exact same fault with a toshiba if im right the backlight fade is slightly gradual but it displays exactly the same symptoms as inverter failiure .dave
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Hi folks,
Had my first 17IPS10-3 and 17MB25-3 set in today. Backlight comes on, then after 2 seconds blue LED lights up on LVDS then backlight goes out followed by blue LVDS led.
Note that there is but one inverter tranny and it reads the same on both secondaries.
Secondary caps look good and diodes check OK.
Any thoughts ? - Thanks - Chris
hi guys
i have same problem i was test all electrolytic cap with my esr and all are good hoping any help will be much appreciated :c017:
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have you checked the 5pf 3kv disc ceramics on the inverter o/ps ??
i have had trouble with these in this model
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^ yes tried to change no luck.any suggestion it may help.
thanks a lot mate
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please just check to see if there is an active backlight control in the menu and switch it off the symptoms are identicle to a toshiba problem i had .dave
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Hi Dave and thanks,
Screen is lit only for a second or so, therefore no time to check menu. Think to go for Fixitnow's 5 puff caps as they were a prob on some other IPS using 12pf (got heaps of 'em) - two in series I guess for a try.
Thanks again all - Chris.
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chris are you running a signal through when testing as the tosh i had would fade when no signal was fed but as soon as signal was introduced it would work fine unless it was end credits where it would fade again
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Hi folks,
Got my 5pf 6kv caps in from China and replaced C230 and C231 - set works - will see - Chris.
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hi
chris this as been discussed a few times over the year on previous
listing supprised you have downloaded info?
dave
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Hi Chris, Did you resolve this fault? I have the same set with similar fault but it is very intermittant. (set can sometimes run for hours or, like yours only last 2 seconds) I,m about to try crimping backlight connectors. Doug
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Hi Sparky,
You're right of course but the caps job didn't work for everyone so thought to fling it back for current thoughts.
Hi Doug, Had a Sammy 24 monitor in this morning and found both top tubes dodgy. Seems to be some corrosion problem where end solder become crystaline - perhaps a dry ? and the wire burns off. Tubes flash up but inverter senses a fault.
Need some tubes with cheap postage - now't yet on Ebay -
PS - Alba is still working
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Hi Chris, yes I've seen a few small screen sets with duff backlights. I'm pretty sure it's dry connections . I've just changed c230/231 in my Alba & it appears to be fine. I wish I'd examined them under a magnifying glass for dry joints before I removed the old ones as I can't see anything wrong with them. Unless they are breaking down under load! Cheers, Doug
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Hi Doug,
Was initially doubtful when I met the 12pf 3kv on 17IPS01-2. Caps read fine on the meter and looked OK but replacements did the biz - Odd one - Chris.
PS - As to monitor tubes (not only LG - Tony) why is it that just the top ones have end dries and burn out the connections ? - Just curious.