Lg 50pk950 hdmi inputs stopped working

[Truncatedhose]

Re: Lg 50pk950 hdmi inputs stopped working

Try it as a last resort, if you have nothing else to try and don't care if the board gets trashed somehow. Maybe try doing it with the power off first, just in case doing it with the power on causes damage.

Yeah, I worried that it could mess something up, but I would hope/think not. I'm tempted to just sell the TV the way it is where everything works but HDMI.

[kca]

Re: Lg 50pk950 hdmi inputs stopped working

Hello Truncatedhose (et. al.) ~

Wondering ...... Did you ever try hitting that green reset button on your LG 50PK950?

I'm in the same spot as you were (with an LG 60PX950), wondering if this might solve the problem of all 4 HDMI ports returning a "No Signal" message.

If you did try it, did you do so with the set turned off or on? Or, did you try both paths?


Hoping (against hope?) that this might be a simple solution to a frustrating problem. These same HDMI ports appeared to be working about 6 days ago for me. I had to put in Y_Buffer boards, and now I get a great picture but only when I am using the Composite ports and a DVD player.

I would like to try the reset by using the green button (SW700), but would like to hear feedback from you or from someone else first.

(p.s. ~ Lots of folks baked the Main Boards in the oven at 385 degrees for 10 minutes and got these HDMI ports working again (see various internet sites), but I'm holding off on that for a bit).

[Nick's Tvs]

Re: Lg 50pk950 hdmi inputs stopped working

The person that did the baking is on the right track but DO NOT DO THAT! I have seen countless people do this and destroy their boards beyond economic repair. I have also seen a lot of people not destroy their boards but only temporarily fix them.
THIS IS EXTREMELY COMMON for both the 50 and 60 inch models. You have cracked solder joints on the main BGA chip of your main board. You will need to rework that chip in order to fix that issue. Some people will reflow their board either with an IR heat element, hot air, or with an oven. What a reflow essentially means is you are heating up the main CPU chip also called a ball grid array (BGA) chip to the solders melting point. When you do that the heat placed on those solder balls which make the contact between the board and the chip will start slightly expanding, and if done right expand enough so that the contacts can be made again. This however is a temporary fix and the cracks in the solder joints will come back very soon as the contact they make won't be what it should be. Sometimes this repair will last a few days, a few weeks, and if done by someone with experience a few months all the way up to a year. However the only way to truly fix this would be to fully remove the chip from the board and rework the chip. This implies removing all the old solder from the board and the chip and placing new solder balls on each contact point.
This is a time consuming process and you will need very advance skills for this along with expensive equipment. The payout however is usually factory quality or better if you use higher quality solder (we do)
If you look at the link below, here is a link to a repair service that will do that rework for you.
Let me know if you have questions
http://www.nickstvs.com/store/p1395/EBR61125901
http://www.nickstvs.com/store/p1396/EAX62563602

[rccrasher65]

Re: Lg 50pk950 hdmi inputs stopped working

99% of the time, bad HDMI is surge damage to HDMI receiver IC, which unfortunately is quite diffficult to replace, without replacing whole main board.

I have successively repaired 2 LG 60 PK750 main boards with no HDMI by replacing the 144pin HDMI switch ic, also checked all resistors in line with IC. Need to do under magnification with hot air and drag soldering. all the ports gave no signal but component side worked. Definately need soldering skills+equipment.

[rccrasher65]

Re: Lg 50pk950 hdmi inputs stopped working

Nicks tv is exactly correct with solution and advice for permanent fix. My boards problems were the Hdmi switch ic's. could be either or, But BGA rework or reballing the chip is the only correct fix. My BGA chips were fine.

[Nick's Tvs]

Re: Lg 50pk950 hdmi inputs stopped working

As rccrasher65 suggested, indeed that IC can be bad and cause the issue, and we have seen that happen in the past. I am not 100% sure what readings you are supposed to get on this model as it is the weekend and I am typing from home, but usually when those IC's go out we tend to see shorted capacitors around those chips or very low Ohms reading on them. You could also try to remove the heatsink and heat up the BGA chip with hot air for about 30 seconds, let it sit for 5 to 10 seconds then plug in the TV and see if the HDMI temporarily starts working. If they temporarily start working, then you know the BGA chip will need rework. If the heating doesn't work however it doesn't mean it still isn't your problem as that trick doesn't always work.