Proscan led tv no picture

[osmaidy]

Greetings,

I have a ProScan LED TV, model PLDED5030A-B-RK and it has sound but no picture. I figured the LED driver board probably needs replacement but when I purchased a replacement from ebay, it did not work. I am getting 24 volts to the driver board from the power supply board but that is about all I can tshoot.

Is this the proper logic or is it possible the LED strip is defective? I suppose it is possible somebody sold me a defective driver board but not sure if I should try to sink any more money into this set. The voltages on the power supply board are reading properly like at the ribbon cable connectors.

[dskall]

Re: Proscan led tv no picture

Do you see image on screen with flashlight? Do you see a flash on screen when you first power on? You have no backlights correct?

[osmaidy]

Re: Proscan led tv no picture

No image on screen with flash light that I could tell. The screen comes up with the ProScan splash screen when I power it up but then it goes to black screen right away.

[dick_barton]

Re: Proscan led tv no picture

If you have an image on the screen when you first switch on then you need to check the voltages at the led connector at switch on. They may rise quickly but just as quick fall to a lower value.
It could also be that the mainboard is turning the leds off but without any voltage readings there's no way to tell.

Some picture of your boards would be helpful and also the voltages on the power supply low voltage connectors.

[Andrew F. Ali]

Re: Proscan led tv no picture

Most likely LED backlight strings have shorted LEDs. So the backlight will come on and then the Driver will sense overcurrent and shut down power to the Backlights.

[osmaidy]

Re: Proscan led tv no picture

I did check all the voltages on the main power supply board and they were all valid readings like for 5 V and 12 V and whatever other voltages were labeled on the connectors.

I also had 24 V getting to the LED driver board. I checked that right at the connector on the power supply board heading to the LED driver board so voltages are stable.

I suppose this means I have bad LED strips.

[budm]

Re: Proscan led tv no picture

The Boosted Voltage for the LED will be a lot higher than the 24VDC, but since we do not have the pictures of your board so we do not know exactly what you have in your TV.
http://www.shopjimmy.com/catalogsear.../?q=PLDED5030A

[dick_barton]

Re: Proscan led tv no picture

It's the connector connected to the Leds themselves which is located on the led driver board that you need to check the voltages on.

Can you supply photo's of your boards