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Equipment Repairs => LCD TV forum => Topic started by: zoz on January 21, 2012,15:21:38

Title: Hitachi L42VC04U H Stuck in Stand by
Post by: zoz on January 21, 2012,15:21:38

Hi everyone,         :sign0144:
just joined your site and hope your can help a newbie out here....

I have a Hitachi L42VC04U H that purchased at a prety cheap price as it only came on for 20 mins then the display would go multi coloured.
problem seemed to be dodgy lcd panel tape joints which I seemed to fix.
Set work ok for a while then display became pixelated.
Tried to turn back on the following day and would not come out of stand by.
Fault as follows
Turn power on
Stand by comes on (red led) then off
then blue led flashes very fast then off
and then back to steady red

Any help would be much appriecated

Thanks in advance Zoz

 :08:

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: jimca007 on January 21, 2012,17:08:26

Unfortunately stuck in standby is prob the most common fault you get on these flat screen tv's it can have many causes but due to the fact you have picture distortion prior to the fault it would have me thinking the power supply's faulty. try the usual , make sure you've not disturbed any cables going to/from the psu during your previous repair,inspect the soldered connections on the rear of the psu for dry joints/burnt tracks/blow marks and take a good look at all the capacitors on the psu for bulging/leaking. if all that seems ok you need to get a diagram for the PSU being a hitachi there's a fairly good chance it'll be a vestel psu get the number off it and maybe one of the guys will have a diagram to let you check the voltages.... and on it goes ....!

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: zoz on January 22, 2012,04:26:28

Thanks for quick reply.    :c017:
 The power board is a Vestel 17PW26-4 v.1

after a late night of changing caps on this board the problem remains I did notice that I do have the opto sound alight on the main board.
What next...?
Drawings anyone or pinout voltages.........  :thumbup:

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: jimca007 on January 22, 2012,04:45:55

here you go

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: zoz on January 22, 2012,05:28:41

Thanks Jimca007
Im just checking my board and it doesnt seem to match....??!!

I have a plug connection marked PL816 which is a 28 way connector to the main board, I can't find this on the drawings...different version maybe.

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: zoz on January 22, 2012,09:19:34

UPDATE
just chucked it all back together..again
Powered up ok but screen had green and some red pixs all over. (random pattern)
No sound though
turned off again and now reverted back to same problem red standby, then the flashing blue back to steady red.
Arggg

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: cdel on January 23, 2012,17:51:35

hi,
think there's a problem on the power board and main board as well.

Title: Re: Hitachi L42VC04U H Stuck in Stand by
Post by: alii_123@hotmail.co.uk on January 12, 2022,08:33:21

Hello,

Can you advise me , I have the hitachi l42vc04u H
It changes from red to blue light momentarily, but returns back to stand by.
If I hear the board with a hair dryer it will go in to full power and stay on.
Any advice please?

Thank
You alex