LG 52LB5DF-UC Screen color washed out

[Glassman]

LG 52LB5DF-UC Screen color washed out.
S/W Version V03.32.01
Micom Version V03.07.0
UTT15357
PQ Version V00.10.10
PQ Model: L52LB5DFUC
Power Board Model - FSP455-6Fo1
Main Board - EAX32740504
Tcon Board - 6807C-0175C
A friend gave me this TV a few weeks back; it has been sitting at his house for awhile. When I got it home, I hooked it up and everything looked great. Within the hour, the screen went white and the colors were all washed out. It also had some coil or cap whine. When I opened it up, I found a couple of small bulged caps. Replaced those and it still had the same problem but the coil whine was gone. I cleaned the ribbon cables up (the ones from the Tcon board to the screen and the cable from the main board to the Tcon board, powered it up and it had a red hue to it with a red line down the left side. I reseated the cable and it looked great again. Same thing though, within the hour it was back to a washed out picture. Since then I haven't been able to get the colors to come back. I also haven't had it unplugged more than a couple of hours. I checked the voltages coming from the main board to see if any of them where being dragged down by a short and they all looked good. I did notice a noise coming from the main board, but it went away when I unplugged the cable going to the tcon board. I also unplugged one ribbon cable at a time on the tcon board to see if the screen was causing the problem, which didn't make a difference either way. I'm also able to get into the factory setting, just not sure what to do in there, so I left it all alone. I think it's the Tcon board that is bad, but I don't know for sure. I'm hoping someone can give me some guidance on what else I should check to confirm this. I have also included the service manual that I found.
Thanks for any and all help,

Voltages from Power Supply
Pin # P202____TV Power On_TV Power Off
1 ACD_____5.061_______5.076
2 PWR On__3.006_______0.006
3 5v ______5.063_______5.097
4 GND
5 I-C______3.104_______0.006
6 ERR______3.196_______0.054
7 BRI______1.602_______0.053
8 5v_______5.063_______5.097
9 GND
10 PWM_____1.342_______0.015
11 6v_______6.046_______0.001
12 GND
13 3.4v on___2.525_______0.006

Pin # P201 TV Power On TV Power Off
1 19v______19__________0.009
2 19v______19__________0.009
3 GND
4 GND
5 6v_______3.047________0.001
6 GND
7 3.4______3.462________0.115
8 GND
9 12______12.07________0.009
10 GND

[mmartell]

Re: LG 52LB5DF-UC Screen color washed out

I would guess tcon as well but try unplugging the small dimming ribbon from the tcon first to see if that helps.

[budm]

Re: LG 52LB5DF-UC Screen color washed out

That looks like GAMMA Voltage problem but I do not see any GAMMA Voltage test points on that T-CON board.

[Glassman]

Re: LG 52LB5DF-UC Screen color washed out

I unplugged the small dimming ribbon from the tcon and it didn’t make a difference if it was plugged in or not. Just to make sure I was doing the right thing, the dimming ribbon cable is the small cable on the left side of the tcon board?
Thanks for your help,

[mmartell]

Re: LG 52LB5DF-UC Screen color washed out

Yes you got it right. What board were the replaced capacitors on ? I would use a freeze spray (upside down can of air) on the tcon, starting at the main processor and see if you get the picture back.

[budm]

Re: LG 52LB5DF-UC Screen color washed out

That dimming cable is for the local dimming for the fake high contrast ratio spec, it will not cause washed out pictures.

[Glassman]

Re: LG 52LB5DF-UC Screen color washed out

The two capacitors I changed were on the power supply board. I marked them in red on the photo, they were 220uF 25v.

I'm pretty sure, to almost positive that it's the Tcon board; I hooked everything back up and tried the cold spray, nothing changed at all. I figured I didn't really have anything to loose, so I heated all the IC solder points up with a heat gun. Now the TV is working almost great again, except for the right side where there is some ghosting. Tried reseating the cables but that didn't help. (Photo enclosed) I went and looked at it again its back to the way it was.

I looked for quite awhile last night, I think I found a new board. The sight has 3 boards listed and I think they would all work but only one of them is in stock. These are the ones listed http://www.tristatemodule.com/t-Sear...?q=6870c-0175c this is the one that is in stock http://www.tristatemodule.com/p-1426...lfhdtv10a.aspx , do you guys think the one that is in stock would work?

Thanks for your help