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Ask Aric Your Own Question
Aric
Aric, Technician
Category: TV
Satisfied Customers: 41954
Experience:  15+ years in the field. Owner of AV Installation, OEM and Repair company
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My tv has no picture or sound but the power lite works

Customer Question

My tv has no picture or sound but the power lite works
Submitted: 1 year ago.
Category: TV
Expert:  Aric replied 1 year ago.
Hello and sorry you're having problems. I may be able to help, but I need to ask for more info.
1) How long have you owned the TV for and when did the problem occur?
2) Does the screen light up when the power button is pressed? Or does the green light and TV remain EXACTLY the same when power is pressed (no response at all)?
3) Additionally has any work ever been done on this TV?
Customer: replied 1 year ago.
I turned it on and it came on! It goes out after some random time and does not come back on.
Customer: replied 1 year ago.
Now the screen went black but there is sound
Expert:  Aric replied 1 year ago.
Thanks for the reply.
If the picture came right back on, it could be due to the cable box, HDMI cable, or the TV itself.
Was the screen still lit when the set was showing no picture and no sound?
If not, were you able to pull up MENU or change Input- or anything?
If not, then you have an intermittent fault in the TV- which isn't uncommon when parts start to fail.
If there was no response from power (no change in screen, no click no change in power light, etc.), then you're usually looking at needing the Mainboard replaced eventually. This is an average of $250 parts and labor.
If the set clicked on however, and nothing displayed on the screen- and no sound, then this is more in line with a power supply board fault occurring- and is around the same cost.
If you run into the issue again, or more frequently and it doesn't turn on- then you can use the link below to locate a tech in your area if you'd like:
www.tvrepairpros.com
Alternatively if you're a DIY type and have a multi-meter I can also help you perform your own repairs.
If you need further assistance let me know. Please do not forget to click a POSITIVE RATING before you go- as it's how I am credited for my work. You can follow up at any time, at no additional cost.
Customer: replied 1 year ago.
Now the screen is back. I hate intermittent problems!
Expert:  Aric replied 1 year ago.
I just saw that. Please see my post just above this one.
Customer: replied 1 year ago.
I am a dyi tech guy all my life. I downloaded the service manual for this tv. Is this what you were going to guide me through troubleshooting?
Customer: replied 1 year ago.
Yes, I have a multimeter
Expert:  Aric replied 1 year ago.
I don't use the service manual myself, but rather a meter and the test points on the power board as well as the symptoms.
Now you said there was sound and no picture:
1) Was the screen black as if the set were off?
2) If there was a slight glow (prime), would anything display (MENU, Input source, etc.)?
Customer: replied 1 year ago.
The TV is working now, but for how long?...
Yes, the screen was black as if it was off.
Expert:  Aric replied 1 year ago.
We have to grab those voltage readings (Va and Vs, as well as 15 volts and 5 volts DC) off the power board WHEN the TV is not working properly, but is plugged in and turned on.
What we can do initially, is check all capacitors on the power supply board for signs of bulges, swelling or leaking in the meantime. The test points for voltages are stamped on the power board.
Customer: replied 1 year ago.
It is only a matter of time before it happens again.
I will do the testing the next time this happens. I hope it is soon I find the solution!
Expert:  Aric replied 1 year ago.
It takes as long as it takes, once the unit shuts down, knowing what voltages are present, and which are not, are key in narrowing down the culprit further.
Customer: replied 1 year ago.
This can take some time. Conditionally, thanks.
Expert:  Aric replied 1 year ago.
You're welcome and I can understand that. I'll be signing off for the night soon (been on for about 9 hours today so far), but will be back on tomorrow afternoon (have a morning job to tackle).
Customer: replied 1 year ago.
Will I be able to test the board with the back off?
Expert:  Aric replied 1 year ago.
Yes, the back needs to be removed.
Customer: replied 1 year ago.
There are no interlocks for the power?
Customer: replied 1 year ago.
Yes, I know you have to take the back off...
Customer: replied 1 year ago.
I assume the back can come off and the will be able to be powered on. Thanks
Expert:  Aric replied 1 year ago.
I gotta run, like I said. Will be back tomorrow. I've opened the question in the meantime- others can help if able.
Customer: replied 1 year ago.
Have a good night
Customer: replied 1 year ago.
Now the lower half of the screen black.
Expert:  Aric replied 1 year ago.
I'm sorry for the delay, I've had other jobs to attend to. Now, yes the back can be removed and the set plugged in and powered on. Then you will set your meter to DC volts, ground the black probe to the metal frame of the TV, and use the red probe to test the points on the power board labeled Vs and Va. Let me know what you get please.