Sharp LCD LC-70LE660U

[Vxavier]

Powers up back lights flash, I replaced the Tcon Board
First power up worked great turned it off then back on no picture again.
Unplug and reset ribbon cables powers up and works fine, Power down and
back on nothing.

Any idea where to start on this?

[dskall]

Re: Sharp LCD LC-70LE660U

Need good clear straight on pictures of back of tv with cover off and each board.

[Vxavier]

Re: Sharp LCD LC-70LE660U

Here they are, Thank you for the assist!

[dskall]

Re: Sharp LCD LC-70LE660U

No picture as in no backlights. No image on screen

[Vxavier]

Re: Sharp LCD LC-70LE660U

The back lights flash then go off with no image on the screen.
But if I disconnect and reconnect the Tcon board the back lights come on and I get picture
As soon as I power it down and back on the back lights flash and no image

[maxvalutech]

Re: Sharp LCD LC-70LE660U

Not clear on what cables you are referring to on t con are they screen or main board ?

[Vxavier]

Re: Sharp LCD LC-70LE660U

The 2 flat ribbon cables that goto what I'm guessing is the led drivers

[maxvalutech]

Re: Sharp LCD LC-70LE660U

As far as I know those ribbons just build the picture. If so your actions must be acting as a switch to affect something else. Have you tried disconnecting main board lead to t con to see what that does to backlights. I understand LED turn on voltage has to reach a certain figure then drop back a bit - guys is this correct?. These circuits today can affect one another. Check voltage going to t con usually about 12v. What happens to that voltage when ribbons disconnected I.e. load reduced. Hopefully the people with real knowledge will comment.

[attainteddragon]

Re: Sharp LCD LC-70LE660U

on the connector that goes to your main board, can you take some measurements.
list it as

pin no, pin desc, v in stby, v when powered on, v when it faults




also v on the t-con fuse when running and when in fault mode as max has requested.

[thoma]

Re: Sharp LCD LC-70LE660U

https://www.youtube.com/watch?v=MVGt7pV1-_E

http://www.avsforum.com/forum/166-lc...-thread-2.html