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Lcd Tv Repair Got me Stumped (patience may be required)

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Keshin

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Hey guys been awhile since I've been on, decided to get back into this electronics fiddling again so i pulled out my old lcd tv and have been trying it but no success, if anyone doesn't mind sharing some suggestions etc it would be most appreciated.

So the tv is a LG 37LC7D - AB
Manufactured date December 2007 (I will refer to this further down)

So if i remember correctly years ago it worked then slowly started showing symptoms of failing caps in the way of slow to turn on to eventually not turning on.
i then purchased new caps and replaced the blown ones (was recommended to put a higher voltage cap but same Uf cap in)
After i did that i still had no tv, and it ended up in the cupboard for the last 2 years

Now yesterday i pulled it out and decided it was time to fix it so i went again and purchased all new capacitors for it and replaced every one on the board, again no success. I researched and found LG put out a "LG rework bulletin for 2007 TV models" which states The following.

All 7D series boards except 47LC7d Remove the coils with ref# L4010, L4011, L4012, L4203, and L4206 and install jumper wires.
• L4206 is not mentioned in any of the bulletins. This is the coil that is connected to the AC detect line and is causing the dead set and shut down problems and is a very common failure.
• Less common and done on a case by case basis is coil L4204, which is connected to the Inverter turn on line. If you have no backlight, suspect this coil.
• If you see a problem with the volume increasing to maximum on its own, this is not caused by the coils. It is a static suppression zener diode on the keyboard that is shorted.
• Use a complaint code of INSS regardless of symptom and use authorization code RD

Ok so i have searched the boards for these reference points and have had no luck in finding them, At this stage the tv will flash the green light then go solid green and the backlight will illuminate, however i have no picture, sound, or button function. I should also mention once the power is connected it self powers on.

Links to:
TV manual: http://data.manualslib.com/pdf3/76/7521/752096-lg/37lc7d.pdf?062b2aacacd34b3a693d810671258a1a
 

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