Chosen Solution

Hello, my Sony KDL-52W5100 all of a sudden has no backlight and no sound. Things I have noticed and done:  Full power down and disconnect from receptacle. Held power button for 30 seconds to fully drain capacitors. Reconnect to power and I immediately hear a single click from the relay. TV goes into standby. Power attempt reveals solid green LED and Sony letters light up, but no backlight or sound.Connected my PC to the HDMI port and turned on. No backlight or sound however the computer properly detects the external display and labels it as a Sony Bravia LCD.Connected my music player (iPhone) to the audio port and cycled inputs (no indication visually that it is actually cycling through inputs - no audio heard.Played an audio clip on the PC while connected to the HDMI port and cycled through inputs, no audio can be heard.Tried to put the TV into service diagnostic mode: Display - Channel 5 - Volume down - Power from the remote while in standby. LED and Sony logo light up, but no diagnostic on screen and again, no backlight, no sound.Opened the back…no visual problems that I can see such as blown/bulging capacitors. No odd smell.Over the years, I have noticed periodically throughout the day, the TV relay would make an audible “click” when the TV was otherwise in standby mode. I never noticed any lights or indication it was power cycling otherwise. Given the last bullet, I’m thinking power board related? I need to pull the schematic to see if I can detect power to the inverter. Not sure where to take this otherwise? I know this is a 10 year old TV. It really was only ever used by the kids on weekends to play Xbox and while a new 65” is relatively inexpensive, I would like to give this one a solid shot at repair before committing it to e-waste. Any feedback would be VERY welcomed!

Hi, Did you try to go into Service Adjustment mode? According to the service manual (hopefully this is for your model i.e. correct chassis number) it is Display - CH 5 - Vol. Up - Power. The service manual has the schematics and the parts list which should be a help.

hello @mrdp, sounds like youre pretty capable of troubleshooting. just following up on some your post of testing for voltages. if you were to pull the back to test voltage to the inverter, you may want to go ahead and check the voltages that are printed on the power supply board at the connector going to the main logic board and the voltages printed on the power supply either going to your driver board, or if built in, at the connector leading toward your led’s. if these are not present, or are very low or jumping up and down, then it may be the power supply. if the voltages are there and steady from the power supply to the main board, it may be the main board that has failed. this is just a generic response as i dont know what board models are in your particular tv, but this should get you looking in the right direction. if you are uncomfortable working with live voltage, dont. Do this at your own risk.