# [SOLVED] acoustic solutions lcd wont come on help



## johnjgjohn

hi there i have acoustic solutions lcd tv with power board 17pw20 v1 i got a kit from ebay which had 

c877 15NF
c878 15NF
IC829 78L05
Q809 BC337 which i cant find on board
c817 220UF
c801 33UF
c901 4.7UF
c892 100UF
r817 r818 r819

i have changed all accept Q809 which i dont ssee on the board. r817 r818 r819 read as open but when removed from board read619k so i never bothered changing them. the tv led comes on i press the button the led goes off for about 5 secs then goes back on but the screen doesnt light is there any other caps tht might need changed? or what else could be wrong?
please help someone much appreciated
tnx john


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## octaneman

*Re: acoustic solutions lcd wont come on help*

Hi johnjgjohn



From what you posted you do have stand-by power, but the main I.C isn't kicking in. Look at the board again, there has to be an SCR near an opto-coupler that's getting hot and isn't switching on. 

Question: Is Q809 a transistor ?


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## Done_Fishin

*Re: acoustic solutions lcd wont come on help*

@ Octaneman


> Q809 BC337 which i cant find on board


@johnjgjohn .. do you get any sound ?? have you tried changing channels ?? 

My experience of black screens usually boils down to power supply capacitors or the occasional smd fuse in the inverter section for the backlight ..


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## johnjgjohn

*Re: acoustic solutions lcd wont come on help*

hi there yeh its a transitor. i managed to get it fixed i changed both c857 and c818 caps 4700uf and that seemed to sort it all working fine now and aparently q809 is not installed on all boards thts why i couldnt find it lol
thanks guysray:

total repair cost £6.30 happy chappie:smile:


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## Done_Fishin

It seems that the parts you changed weren't even in the parts list / kit you purchased. 

Did the capacitors have bulging tops compared to the ones that you replaced them with ?? That's usually the first thing I look for when I open up any electronic equipment these days.

Congrats on the fix and if you are happy that everything is working fine , you can mark your thread as solved as per my signature below


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## johnjgjohn

yeh i prob didnt need the kit i did notice they were slightly bulged at the top but i wasnt sure wat i was gettin in the kit just saw it n ordered it. n they werent in it i took them from another board i have lying around but ill know next time to check and start with any thats bulging

hw do i mark as solved


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## Done_Fishin

my experience tells me that when you see a capacitor that bulges , even ever so slightly, you change the capacitor(s) first and then look for other reasons if that doesn't work .. 95% of my repairs are cured solely by replacing capacitors these days .. 

just something to bear in mind for the future. 

To mark as solved you look at my signature .. there is a picture .. look for thread tools at the top of the page (as shown in the picture) click on "mark as solved" to put a check mark and then just below click on perform action. 

:wave:


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