Lg led led no picture now

[Mrntd]

The tv is a lg 39ln5700. The screen did have an image with the flash light test. At first we thought it was the power board. We replaced it with no difference.

After reading more here I found a way to test the LEDs to see if that was it. Yep.

Got the 4 strip pack and replaced the 2 bad strips. Before reassembling check to see if it worked. Yep we have light. Reassembled the tv, turned it on and a bunch of vertical lines. Brighter strip in the middle.

Check the ribbon cables and the ends were damaged. Got replacements for those. No difference. Read some more, may be a bad t-con board. Got one of those. Now we have a black screen no image with flash light test.

So now what? It's frustrating that it had an image before we took it apart and now it doesn't. I'm looking for some help.

[comptek]

Re: Lg led led no picture now

any pictures of the fault ?

[Electronic Handyman]

Re: Lg led led no picture now

It's possible that you've some kind of bad connection double check all the plug in connectors connections, Be sure to check the soldering connections on those connections and the rest of the boards.You may even have a faulty PSU I'd try the old one again.

[dick_barton]

Re: Lg led led no picture now

You may have damaged the LCD panel tabs.

It may be worthwhile taking a close look at the tabs that are fixed to the panel to see that they are not damaged.

I have ripped one off when removing/re-installing a panel but thankfully only once and lesson learnt.

[Mrntd]

Re: Lg led led no picture now

It would just be a picture of a black screen.

Both PS do the same thing.

Checked the tabs (which are the thin ribbons coming out of the screen, right?) None are torn or or loose from the boards.

Checked all the cables.

Tried the disconnect one ribbon cable from the t-con to see if I got a half screen difference. No change.

Even though the screen shows no damage could it have flexed too much while we replaced the LED?

[ReeceyBurger123]

Re: Lg led led no picture now

You are getting backlight right ?

[Mrntd]

Re: Lg led led no picture now

Yep. Back light is working fine.

[dick_barton]

Re: Lg led led no picture now

Can you post some sharp images of the circuit boards.

[budwich]

Re: Lg led led no picture now

When you say "cable ends damaged"... what does this mean... pictures? might provide some clues as to what you are battling... poor connection OR "shorted positioning"?

[dick_barton]

Re: Lg led led no picture now

Tcon. How were you connecting the flat cables. There are clips which have to be lifted upwards, then attach cable, next clip back down again to lock them in place. Or are you pushing the cables back into the connectors?

[Mrntd]

Re: Lg led led no picture now

I did push it in the first time. That is what damaged the flat cables. The contacts pealed back. The second set of flat cables I put in right flipping up the latch sliding it in and closing it.

[budwich]

Re: Lg led led no picture now

hmmmm sounds like you need to "re-examine" your "work". IF you were trying to install those cables in the manner you just described, then it is quite likely that you might not understand how the cables are meant to be aligned in the connectors. Their alignment has to be very precise... there are small tabs on each side that need to be followed. Hopefully you haven't damaged the connector receiver portion.