Panasonic TX-L47E5B Image Problem?

[dick_barton]

This set has me completely puzzled.

The set appears to have the standard solarized image problem.

A replacement TCON board arrived today and after installing it to my surprise I had exactly the same solarized picture.

Lifting the panels right hand side tab from the tcon, I have a clear bright white picture on the right half of the screen with the left half grey.
Replacing the tab and lifting the panel left hand tab from the tcon, I have a bright white picture on the left half and lines down the screen on the right side.

There's also a wide vertical bar (light in colour) which can be seen in the photo's where an image is displayed that appears to fade in and out on the left side of the screen.

The menu on On Screen images all display perfectly.

Any idea's welcome

[vinceroger69]

Re: Panasonic TX-L47E5B Image Problem?

maybe a faulty lvds cable? its odd the menu is fine could it be a mainboard bga fault? have you done a factory re set and tried lvds settings in the service menu

ive just read a post where tom says this
Changing the LVDS format will mess up the colours. BUT, if it messes up the whole picture, it is the main board at fault. If it only messes up the background image, it is a T-con fault.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Hello Vincerogers,
I've done a factory reset and also downloaded and installed the latest firmware. There's a possibility that I have purchase a faulty Tcon but I'm doubting this because the fault is identical with both boards.

The mainboard BGA fault is a possibility because I see the feint line ( 2" to 3" wide) down the screen when there is a picture but is not there when there is no image to display.
Thanks for the information.

[vinceroger69]

Re: Panasonic TX-L47E5B Image Problem?

maybe worth trying a bit of heat on the mainboard chips see if that helps i doubt its another faulty tcon too but i guess if its a common fault you cant rule it out. Do panasonics suffer tab bond issues? these are just my thoughts reece/budm etc may have more ideas what may cause this fault.

[ReeceyBurger123]

Re: Panasonic TX-L47E5B Image Problem?

maybe a faulty lvds cable? Its odd the menu is fine could it be a mainboard bga fault? Have you done a factory re set and tried lvds settings in the service menu

ive just read a post where tom says this
changing the lvds format will mess up the colours. But, if it messes up the whole picture, it is the main board at fault. If it only messes up the background image, it is a t-con fault.

+1 bga solder IMO

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Thanks once again for your replies.
What's the most reliable home method to redo the BGA chip. I have a hot air station and a thermocouple meter so that I can monitor the chip temperature. An idea of temperature(s) and time(s) would be welcomed.

[diif]

Re: Panasonic TX-L47E5B Image Problem?

Thanks once again for your replies.
What's the most reliable home method to redo the BGA chip. I have a hot air station and a thermocouple meter so that I can monitor the chip temperature. An idea of temperature(s) and time(s) would be welcomed.

I had a Samsung Smart TV last week with dodgy BGA (no picture until i pressed on it).

I stuck the board on my rework machine, I used the bottom heaters to warm the board then my hot air station to reflow from the top after putting some quality flux on all four sides.
I used my backup thermocouple and got the top to about 230C and held it for a few seconds.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Thanks for your help there diif. Appreciated.

[sordids999]

Re: Panasonic TX-L47E5B Image Problem?

Try reflowing your BGA nothing to lose i have just fixed a 60 inch Sharp the same way it sounds wrong compared to a rework station but i use a dremel torch and some TOPNIK tk83 Flux always works for me
so far done a 47 inch LG led bad BGA (lines all over the screen and tv switching off) still working on my wall 9 months later and a few more tvs for friends all still working

good luck

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Again if I can ask what temperature and time you normally run at.
There are components on the top side of the BGA module so these may prove to be a nuisance, however I can cover them with Kapton tape to stop them flying off.

I've found a supplier on ebay selling a replacement board which is not too expensive so if it fails I can order it.
Thanks

Edit
The problem may well be the BGA chip because it's linked to a heatsink using a thermal pad and the heatsink is held in place using plastic clips. The pressure applied to the chip is abysmal and the heatsink virtually floats freely above it.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

It did look like it was a BGA problem. After heating up the BGA chip the picture would flick between OK and solarized.

Decided to have another go and successfully killed it.

Replacement board on order.

[ReeceyBurger123]

Re: Panasonic TX-L47E5B Image Problem?

Ok thanks for update, now we know bga is a common issue. I advise you put in some prevention methods-ie bigger heatsink with better thermal compound or thermal pad under the board or even a fan but probably over kill.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

+1 Yes it definitely needs a better heatsinking solution. As I said the current method is close to useless.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

I have finally resurrected the TV again. Both the main board and tcon have been replaced however there is absolutely no difference in the display.

This is now leading me to conclude that the panel must be at fault.

The picture still displays a solarized look but generally only on the lower half of the screen and this is accompanied by flickering brightness, again only in the lower half of the screen. The backlights when viewed from the rear are steady and do not appear to be flickering.

When entering the service mode Self Check routine everything seems to be OK but it does give an SOS 1, but I do not know what that is referring to.

Interested in anyone's thoughts before I split the set up for spares.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Just one last observation. When the screen is displaying the auto tune menu and occupies the full screen space, the picture is perfect. No solarization or flickering.

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

All done and the set is now up and running as it should.

Due to my reluctance to strip down to the panel when looking at it previously, I reckoned that now I had nothing else to lose so decided to take a look at the tabs. So off came the side strips to gain access and what do I find; only what appears to be some tacky brownish gunge similar to Marmite, across one of the tabs.

Cleaned it all off and run up the set for a perfect picture.

I could kick myself for not looking earlier especially since there was always a top to bottom strip on the screen about 4" wide in line with that tab that was showing up whenever the picture content was dark.

[Moreno83]

Re: Panasonic TX-L47E5B Image Problem?

I've seen a lot of these E5 models lately but i thought it was panel problem so i left them as is....
Just saw this Panasonic E5 tv. You reckon its the same fault ?

EDIT: Wrong picture , picture coming soon :p

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

Decided not to sell it and now use it as my main set. Really happy with it

[Moreno83]

Re: Panasonic TX-L47E5B Image Problem?

You reckon this is the same?

[dick_barton]

Re: Panasonic TX-L47E5B Image Problem?

It certainly looks extremely similar except in your picture it looks a lot more noticeable than say in the 1st picture, Post#1.
The other thing that was very noticeable was that the picture would also look solarized dependant on image displayed. See picture 3 where the thick line goes through her hair.