Hi all,
I bought this TV from eBay with the intention of fixing it for myself. The seller claims that the TV takes a long time to switch on although I've yet to have it switched on!
Basically when you try to turn it on from standby, the red light blinks a couple of times and then turns off. The screen does not come on nor does the LCD back light. I took the back cover off and and immediately noticed a faint buzzing from the PSU board. After some detective work involving a plastic pen between the suspected components and my ear, I localised to buzzing to be from a Metallised Polyester Film Transistor (CP812). The capacitor only buzz when the TV tries to switch on but not in stand by.
According to the schematics, this capacitor is part of the Power Factor Correction circuitry on the DC side. I am unable to identify what the value of this capacitor and would like some help on choosing the correct replacement. All it's written is 2W 105K SIC 460S.
Is it unusual for the Polymer cap to fail? I heard these tend to be pretty reliable. I haven't tested the electrolytic capacitors but they all look fine to me and I don't particularly want to start de-soldering components unless I get more evidence that the failure is from the electrolytic caps.
Picture of the PSU board is attached and schematic is on page 93 http://loraart.ru/LE32C550J1W_Service_Manual.pdf
Edit: I removed the cap from the board and tested it. It's reading 958.2nF.
I bought this TV from eBay with the intention of fixing it for myself. The seller claims that the TV takes a long time to switch on although I've yet to have it switched on!
Basically when you try to turn it on from standby, the red light blinks a couple of times and then turns off. The screen does not come on nor does the LCD back light. I took the back cover off and and immediately noticed a faint buzzing from the PSU board. After some detective work involving a plastic pen between the suspected components and my ear, I localised to buzzing to be from a Metallised Polyester Film Transistor (CP812). The capacitor only buzz when the TV tries to switch on but not in stand by.
According to the schematics, this capacitor is part of the Power Factor Correction circuitry on the DC side. I am unable to identify what the value of this capacitor and would like some help on choosing the correct replacement. All it's written is 2W 105K SIC 460S.
Is it unusual for the Polymer cap to fail? I heard these tend to be pretty reliable. I haven't tested the electrolytic capacitors but they all look fine to me and I don't particularly want to start de-soldering components unless I get more evidence that the failure is from the electrolytic caps.
Picture of the PSU board is attached and schematic is on page 93 http://loraart.ru/LE32C550J1W_Service_Manual.pdf
Edit: I removed the cap from the board and tested it. It's reading 958.2nF.
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