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Electronics => Repair => Topic started by: DTJ on January 07, 2023, 06:04:01 am

Title: Sony TV KD55X8500G power on issue - schematics? ideas?
Post by: DTJ on January 07, 2023, 06:04:01 am

My 3 year old Sony TV shutdown unexpectedly the other night and now will not power on. The factory reset doesn't work either. It appears completely dead.

I found a service manual for an earlier variant online at https://servlib.com/sony/tv/kd-55x8500a.html?start=0

Being completely dead had me hoping it was just a fuse or similar but I cannot see anything obvious.   :--



Before I started poking around further I wondered is there such thing as schematics available for these things?

If so where will I find them?
Thanks

Title: Re: Sony TV KD55X8500G power on issue - schematics? ideas?
Post by: fzabkar on January 07, 2023, 06:22:15 am

https://elektrotanya.com/showresult?what=KD55X8500G&kategoria=All&kat2=All (https://elektrotanya.com/showresult?what=KD55X8500G&kategoria=All&kat2=All)

Title: Re: Sony TV KD55X8500G power on issue - schematics? ideas?
Post by: DTJ on January 07, 2023, 06:40:28 am

Excellent. Thanks Frank. No detail schematics but much more information than I had.
Cheers.

Title: Re: Sony TV KD55X8500G power on issue - schematics? ideas?
Post by: DTJ on January 08, 2023, 11:11:11 am

Follow up for posterity.

The 3V3 stay alive rail was not present.

It had a DDA010 switching supply chip driving a transformer followed by a schottky rectifier.

The SB260 schotty had failed S/C. I replaced it and it now works ok.