Sony 55X8500E no power

[nomoresonys]

Re: Sony 55X8500E no power

can test the tcon fuse, but seems like mainboard issue because of result in post 13, according to that manual, see that flowchart.

[nomoresonys]

Re: Sony 55X8500E no power

do you have any voltages at all on the mainboard?

[wumeow]

Re: Sony 55X8500E no power

The zener diode is in parallel with low-resistance resistors, so it seems to you that it is short.

That's right, thanks.

[wumeow]

Re: Sony 55X8500E no power

in some cases you need to jump power-on, bl-on, and maybe all the pwm pins to stndby to get the backlights on.

Are they all jump with 1K resistor?

[wumeow]

Re: Sony 55X8500E no power

do you have any voltages at all on the mainboard?

I did follow the flow chart on the service manual. but not sure what is the root cause.

Getting 0V on both R441 and R527, which suggest IC401 is faulty. At the same time, I also get 0V on C400-C412.

Would you shed some light please? Thank you.

[nomoresonys]

Re: Sony 55X8500E no power

Are they all jump with 1K resistor?

yes I think 1k should work.

[nomoresonys]

Re: Sony 55X8500E no power

I did follow the flow chart on the service manual. but not sure what is the root cause.

Getting 0V on both R441 and R527, which suggest IC401 is faulty. At the same time, I also get 0V on C400-C412.

Would you shed some light please? Thank you.

mainboards are tough because of how many ways they can go bad and how hard they are to work on, I spent several hours and money on components trying to fix my sony mainboard a few months ago but failed miserably.

[nomoresonys]

Re: Sony 55X8500E no power

maybe check out Nick's tv on youtube, hes a tv fixing maniac.

[davidpringle]

Re: Sony 55X8500E no power

Did you replace ZD905