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Old 07-20-2017, 11:10 PM
Findm-Keepm's Avatar
Findm-Keepm Findm-Keepm is offline
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Join Date: Jun 2007
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On the 32-inchers, a common intermittent problem is on the A (main board) - the connectors on the board develop bad solder joints - the heat/cool cycle affects them greater because the mass of the pins is greater than the typical component lead. The connectors will all have a "CN" prefix.

I stealthily fixed one in my ex-in-laws timeshare. We had a service call in, but there had to be someone there to "host" the tech - yeah, right. So I got help, manhandled it over to the table, pulled the back, and went to work re-soldering with a butane powered iron at first, and then a RadioShack iron second. About 20 or so really obvious bad connections repaired, and it was fixed. Dora the Explorer for the kiddo...

Take a good look at all the chip connections to - the uP resonator and the microprocessor IC itself (big chip, center of board with 56 or 64 pins..) - they can cause all kinds of problems. Don't flex the board looking for bad connections - you can corrupt the EEPROM and start a whole new set of problems (DAMHIK) - use a good quality magnifier/loupe to inspect the A board connections.

The only other intermittent shutdown I'm aware of in the XBRs is the audio chip TA82XX (not sure of the suffix...) will start into overcurrent/overheating and shut down a set. You can run it at low volume for hours, no shutdown. Raise the volume to room volume, and wait a minute or two, and bam - shutdown. Sony also advised replacing the diode feeding it B+, and we did change a few of them as a precaution.
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Brian
USN RET (Avionics / Cal)
CET- Consumer Repair and Avionics ('88)
"Capacitor Cosmetologist since '79"

When fuses go to work, they quit!
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