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#1 |
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Join Date: Dec 2020
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![]() Hi guys,
I've just received an 10 years smart LG 47LE8900 from a friend and i can't seem to find out why i don't have any image or sound . It has only stand-by light . I have checked all voltages on the power board, I have cleaned all ribbon cables, i have checked all fuses , i have done a visual inspection on all capacitor and they look ok. I've attached some pictures with all the boards. Give me some idea's what can I do to get it working again. Thank you, Last edited by SMDFlea; 09-12-2021 at 07:47 AM.. Reason: LG 47LE8900 |
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#2 |
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![]() Very often these LG suffers from bad CPU soldering. You need to try a reballing from a specialized center, this is one of the best models from LG so it will worth some spending, after made it a new bigger heatsink is suggested, or a fan.. it is not truly old for me..
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#3 |
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![]() They usually do start up if the BGA soldering is bad. Disconnect the cable between main board and tcon. Does it power up then?
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#4 |
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![]() Are you referring to this particular model? Because in other LG it doesn't start..
A quetion, when you push power button does it makes some status led blinks? Last edited by Davi.p; 09-12-2021 at 08:42 AM.. |
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#5 |
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![]() The couple I had to work on would power up from standby but had no picture, no sound.
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#6 |
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![]() I'm talking about this particular model 47LE8900 when i push the power button it turns the front touch buttons on and the logo, nothing else. No backing light or anything else.
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#7 |
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#8 |
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#9 |
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![]() Does the lights blinks or stays on for some seconds and then shuts off? Anyway this doesn't change much, i confirm the diagnosis.
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#10 |
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![]() LE, LV, LW, and LS series suffers from bad bgas. Lot of ebay repair services if you google your model. To confirm, you can heat up the cpu with a hair dryer before plugging in.
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#11 |
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#12 |
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#13 |
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![]() SOLVED !
I have backed the main board at 200 degrees Celsius for about 10 minutes and after i left it cool down I got it back in the tv and i was pleasantly surprised to see that it works (I have done it before with other main board without success ) . Thank you for the support guys! |
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#14 |
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![]() Ley us to know when the problem will return eventually..
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#15 |
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![]() I can source replacement processors for these, the BGA rework side of things is up to you though as I no longer have a rework station.
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#16 |
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![]() The unique the processors that you find are probably second hand..
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