Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

[neilc6]

Was given this repair kit to install but the customer lost the instructions. We both messaged the ebay seller and they haven't responded. Actual board is slightly different rev ZH but looks very similar.

Kit contains a driver IC, fuse and three SOT23 parts.

On the board, there are 3 SOT 23's marked XOVV, COXA, and X7UV.

The kit contains a UDSW6, X7HV and K72 (2N7002, NCH, 60V, 0.21A)

Assuming the X7's are the same. COXA is identified in another thread as likely bad and cross-referenced to A03460 (NCH, 60V, 0.65A) so shoudn't be replaced by a 0.21A FET. By elimination, UDSW6 should replace COXA but can't be sure without identifiying either XOVV or UDSW6.

[neilc6]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

Here are the suspect parts.

[yohnsee]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

Might help, might not:
https://www.youtube.com/watch?v=yTnkOfwBGGE
Sorry, that has nothing to do with the markings. I tought I can zoom in the 1080p video and get the markings

[neilc6]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

Yes this helps. Video says the COXA part is suspect. Measuring drain to source resistance I get 2.8 ohms instead of open which confirms this part needs to be replaced. The video also indicates 75% of this failure is caused by a bad panel.

This thread applies which uses the same panel

https://www.badcaps.net/forum/showthread.php?t=49281

[yohnsee]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

I would love to hear about your progress (if or when you make any)
I think this would help a lot of people in the future with t-con problems.

[neilc6]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

The person I was helping insisted on replacing the tcon anyway since he indicated it was repaired before. Couldn't convince him the fault was in the panel causing the tcon to blow transistors. Too difficult working with him since he also had given me the repair kit without telling me he lost the instructions. I did see the same model TV posted on CL with same problem but now know it is repairable.

The referenced thread indicates a suitable replacement for COXA is RTR020N05TLCT (45V, 2A) available at Digikey.

Ebay seller is probably ignoring us because they know the repair kit fixes the board and NOT the TV.

[yohnsee]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

If I get it right, in a few days/weeks you will have in your hands a perfectly functioning t-con. Then if you would be so kind, could you make a few good quality photos of each? I am just curious, would like to compare the two.
Sorry to hear, that it is difficult to move forward because of other negligent people.

[neilc6]

Re: Sony Tcon Repair Kit RUNTK5261TPZK KDL-70R520A

No. The guy was going to buy another tcon and replace it himself since he only brought me the tcon and repair kit. There are different revs of this board. ZH was the one I had. Repair kit mentions it is for ZK or ZJ. From my pic, you will notice an added 10K resistor on COXA but unsure if this was added afterwards or during manufacture.