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Sharp LC32D44 lcd tv

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astracat:
hi just had one repaired under warranty guy came changed backlight tubes ,cured fault similar symptoms to yours
original tubes had black ends

Contrast John:
Hi All
Managed to sort this one out. The lamp error counter had reached 5 which means the set needed to be started in service mode (hold down input and vol - on tv set whilst applying mains until the letter K appears on the screen, after which press vol - and prog - on tv set to get the service menu). Had no joy doing this though because the ccfl driver IC (BD9883 smd) was going into protection mode and preventing the backlight from operating. To get round this problem I overode the protection by fitting a shorting link across C7558 (smd capacitor) located near the IC. The set would now start in service mode.
Found that there are some test patterns available in the service mode one of which is a grey screen. Selecting this option showed the problem. The area across the centre of the screen was darker than the rest indicating the centre pair of ccfl tubes weren`t working. This chassis uses 10 tubes driven by 5 inverter transformers mounted in line with them, so before embarking on a tedious stripdown I ruled out the possibility of a duff transformer by swopping the centre one with one of the others. No change of course, so I dismantled the unit and checked the tubes and their holders for any visible problems. None were apparent but replacing the tubes cured the problem. Just needed to clear the lamp error and remove the link
Hope this info might be useful and thanks to the above contributors for the input.
Regards
John.

sinclairtv:

--- Quote from: brainstorm on April 28, 2010,05:57:27 ---Hi John,

There is a common problem flagged by Sharp. R8408 smd 0.33ohm (part no VRS-TW2PR33JY)
that can develop a 'crack' or go high resistance. that normally causes no back light with the green led lit.

I will send you a couple of bulletins regarding Lamp contact problems as well

Brian
Can you tell me where this resistor is. Cant find anything starting with '8'. Thanks
--- End quote ---

brainstorm:
Hi

I have emailed you the bulletin showing the position of the resistor,

It might be worth having a word with John, because he had quite an in depth investigation into the fault which I think resulted in a faullty backlight tube

Hope this helps

Brian

chrissie jones:
please can you show me the position of the smd fuse cause i cant find it. sorry to be a pest.

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