How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Aric Your Own Question
Aric
Aric, Technician
Category: TV
Satisfied Customers: 41951
Experience:  15+ years in the field. Owner of AV Installation, OEM and Repair company
24739752
Type Your TV Question Here...
Aric is online now
A new question is answered every 9 seconds

My Sony KDL-40EX401 screen went black and the green light slowly

This answer was rated:

My Sony KDL-40EX401 screen went black and the green light slowly faded out. After being unplugged for a while, it came back on and within a few minutes did the same thing. Then after doing that a few times, the tv stopped turning on with no green light. Took the tv apart and removed the power supply fuse to check it. The fuse was good. Now what?

Hello and thank you for the question.

 

How long have you owned the set for please?

 

Also, are there no signs of life on the TV at all at this point (power light lit, click sound when power is pressed, etc.)?

 

Additionally, what specific voltages did you check for with the TV plugged in?

Customer: replied 3 years ago.

I've owned it since mid-2010. No life (I clipped the power supply fuse since it was soldered in hoping that was the problem. Stupid, I know.) But prior to that, occasionally the green light would light up, but no click sound and still black screen. Other times, the green light wouldn't even light up. The voltages I was checking for are the ones listed on the power supply next to each of the connections e.g. 12V..., 24V...

Thank you. So you have the 12 and 24 volts present. What about the 5 volts to the mainboard, and the 3.3 standby voltage?
Customer: replied 3 years ago.

No, the voltage readings were negligible on the power supply, so I didn't even check the main board.

I don't know what you mean by negligible. Those voltages are quite significant. Don't worry about checking anything on the Mainboard, what I was to know is if the power supply has 5 volts on it anywhere.

Customer: replied 3 years ago.

When I was checking for 12V or 24V hardly anything registered. I didn't check for 5V or 3.3V, only 12V and 24V.

Okay, you didn't state whether or not these voltages were present. So they're NOT present correct?

Let me ask you this, when you press the power button on the TV itself, do any voltages come up and is there any click from the power supply?
Customer: replied 3 years ago.

Correct, when plugged in, hardly any voltage registers on the power supply and there is no green light or red standby light and pressing the power button does nothing. No clicks.

Thank you. You need to replace your power supply board my friend. You should at the very least have standby voltage and the power light lit, and you do not. The board should also give you a distinct click when power is plugged in, and the supply not registering any voltages at all indicates that the board is faulty and would need to be replaced.
Aric and other TV Specialists are ready to help you