Sony 60W630B working fine the other day. Turned it off and it hasn't turned back on since. No power surge or lightning storms. Has always been plugged in to a Monster Power Center HTS2000. I get nothing from the TV when trying to power on; no LEDS, no screen, no sound. I suspect the power supply has failed in some way but don't know where to start troubleshooting. I checked for continuity across the only fuse I could find which was on the primary side and it checked out. All of the caps look ok, nothing popped or cracked. Part number on the PS is 1-474-586-12. It also says Sony GL2 on it. Picture is attached. Where do I start? I have basic electrical knowledge, mostly 120V household power, never really delved into troubleshooting electronics but it's time to start because I'm not pitching a 2 year old TV.

 

Have you searched for a service manual for your model? It'll be difficult to get very far without it.

 

here is a slightly better picture, but if you know nothing about troubleshooting high voltage stuff you will be better off giving it to someone who can troubleshoot it without killing themselves, or to a sony service provider who might be even better. Or try your luck and buy a replacement and see if it helps.
https://www.ebay.com/itm/Sony-KDL-6...1-474-586-12-APS-374-APS-374-CH-/332170433168

 

here is a slightly better picture, but if you know nothing about troubleshooting high voltage stuff you will be better off giving it to someone who can troubleshoot it without killing themselves, or to a sony service provider who might be even better. Or try your luck and buy a replacement and see if it helps.
https://www.ebay.com/itm/Sony-KDL-6...1-474-586-12-APS-374-APS-374-CH-/332170433168

I agree with @kubeek. Trying troubleshoot SMPS type circuits without in depth knowledge is dangerous especially since it deals with high voltages.

 

here is a slightly better picture, but if you know nothing about troubleshooting high voltage stuff you will be better off giving it to someone who can troubleshoot it without killing themselves, or to a sony service provider who might be even better. Or try your luck and buy a replacement and see if it helps.
https://www.ebay.com/itm/Sony-KDL-6...1-474-586-12-APS-374-APS-374-CH-/332170433168

Yea, this was my original attempt for repair, figured I'd give the forum a shot. Sony will charge me more than the cost of a new TV to troubleshoot so unless I find someone who knows what they're doing that wants a hobby project I'll prob. junk the PS, pick up a used one on Ebay for $50.

 

Yea, this was my original attempt for repair, figured I'd give the forum a shot. Sony will charge me more than the cost of a new TV to troubleshoot so unless I find someone who knows what they're doing that wants a hobby project I'll prob. junk the PS, pick up a used one on Ebay for $50.

Then I suggest you fill out your location in your profile information, and there may come someone who lives close and is willing to help you with that.

 

I’d still want to be sure of the diagnosis before dropping $50. Having no LED or any indication is very suspicious of the power supply, I agree, but it really could be something else. I worked on a TV that wouldn’t power up unless the main computer was happy with the status of several subsystems. Only then would it tell the power supply to kick in.

 

I’d still want to be sure of the diagnosis before dropping $50. Having no LED or any indication is very suspicious of the power supply, I agree, but it really could be something else. I worked on a TV that wouldn’t power up unless the main computer was happy with the status of several subsystems. Only then would it tell the power supply to kick in.

I'm thinking that may be a possibility too. I installed the power supply and tried to power it up, to see if there are any indicator LEDs on the boards which may help my troubleshooting. There aren't any LEDs and the TV still wouldn't power up but I did notice the main transformer was humming when plugged in which leads me to believe the board MIGHT not be as dead as I thought; still could have issues on the secondary side of the board however. I am going to see if the service manual indicates output voltages on the harness connectors that I can check. May help me rule out the power supply. I may not have much experience but that isn't enough for me not to try (obviously with safety as the #1 priority). None of us had knowledge on anything until we learned it. I'm always looking to learn more. I'll do some research, see what I can find. I appreciate everyone's input.

 

Service manual for this model:
https://servicemanuals.us/sony/tv/k...8w605b-kdl-48w607b-kdl-48w609b-k.html?start=1

 

I’d still want to be sure of the diagnosis before dropping $50. Having no LED or any indication is very suspicious of the power supply, I agree, but it really could be something else. I worked on a TV that wouldn’t power up unless the main computer was happy with the status of several subsystems. Only then would it tell the power supply to kick in.

Did a little troubleshooting. Found 3.3V output from PS to BAXL board was good which lead me to believe the PS was not getting the signal back from the BAXL to turn on the high voltage. $50 on Ebay and 15 minutes of install time and TV is back and operational.

 

Did a little troubleshooting. Found 3.3V output from PS to BAXL board was good which lead me to believe the PS was not getting the signal back from the BAXL to turn on the high voltage. $50 on Ebay and 15 minutes of install time and TV is back and operational.

That's awesome! Can you provide a little more detail?

 

That's awesome! Can you provide a little more detail?

Sure, service manual troubleshooting flow diagram helped but had to do some additional research to figure out exactly how to check what the flow diagram wanted me to. The power supply sends a 3.3V standby signal to the BAXL board which contains the main processor for the TV. The power supply has the pin configuration etched onto the PCB so I located the 3.3V output pin and checked it with my DMM and read 3.3V. I then plugged the harness into the connector and checked for 3.3V on the BAXL side of the harness to rule out a bad harness; I was getting 3.3V there too. Combination of the service manual and online research was indicating that the BAXL board might not be sending the necessary signal back to the power supply telling it to turn on the high voltage side of the power supply. There were a number of boards available on eBay so I figured I would give it a shot; seller would allow me to send the board back if it didn't fix my issue. Arrived today, installed it and TV came right to life. Basically, it was exactly as you stated in your original post. Thanks for steering me in this direction.