Sumsung Plasma Tv PN50A550 Faulty?

[ivtec]

Hi guys: i have here a Plasma Sumsung Tv Mod. PN50A550 That has this fault shown on This UTube Video
any help or clue would be apreciated

http://www.youtube.com/watch?v=Q5cwn_JfW-0

[tom66]

Re: Sumsung Plasma Tv PN50A550 Faulty?

I assume you've done the standard Samsung procedure and checked for bad caps? The symptoms are very similar to a main board going crazy due to unstable DC.

[ivtec]

Re: Sumsung Plasma Tv PN50A550 Faulty?

I assume you've done the standard Samsung procedure and checked for bad caps? The symptoms are very similar to a main board going crazy due to unstable DC.

Thanks Tom66 for your so quick response appreciate:i
I did not yet test anything cause the tv is not mine and is still at my friends house and before i go to his house and open the tv i want to investigate more
as you can reed on the Youtube responses from other people trying to repair it they had no success, they say they swapped power supply,Main Board,
Y-main,with no success,and some say this is not a Capacitor easy fix.
If you can find anything else that could lid to the solution please post,

[tom66]

Re: Sumsung Plasma Tv PN50A550 Faulty?

It's screaming main board or power supply to me. Especially when the audio was hissing. Only the main board can do that, unless the power supply voltages are unstable, but it's still the main board producing the signal (just under "duress" if it makes sense.) Also, when it was almost OK (picture still a little bit messed up; looked like some columns were shifted) there was -no- functioning OSD; but when it booted properly, the OSD appeared.

[lilmonk3]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Had one of these given to me for free, it was missing the power board.. They had taken it to a repair shop and they told them it need a power board.. The place was going to charge them $200 to repair the power board.. Then the TV place said the board was beyond repair and it was going to be $500 to get a new board.. So they told them no way and took the tv and headed home.. They stopped by sams on the way home and bought a new one.. Well this is probably more they ya all wanted to know.. Well its now mine.. I pulled the back off thinking it was going to be caps.. NOPE.. THE POWER BOARD ISNT EVEN IN THE TV So I ordered a new PWB and installed.. It click on screen glows then recyles ..After awhile of that, it will final show a snowy screen with the small menu window box in the corner then goes to multi colored vert lines with the snow.. They starts the power cycling over.. I really want to fix this, because my LG 50 is suffering from the bad bad red sparkles and I need this to replace it... So have you figured yours out IVtec

[ivtec]

Re: Sumsung Plasma Tv PN50A550 Faulty?

This boards that's what you need, they're not expensive.try the power board first, then if it doesn't solve it get the main board.


http://www.shopjimmy.com/samsung-bn9...za-rebuild.htm

http://www.discount-merchant.com/Sea...show=25&page=1

[tom66]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Careful, the last part is a Y-sustain, not a power supply. Obviously been labelled by someone who doesn't know what a power supply or sustain is...

[lilmonk3]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Well I am pretty sure its the mainboard.. I put a hair dryer on the mainboard and it works great.. But the problem is trying to find a replacement.. OS everywhere

[selldoor]

Re: Sumsung Plasma Tv PN50A550 Faulty?

If it works when you heat the mainboard shouldnt be much wrong ( famous last words) Can you pinpoint a place where to heat to get it working- what
components on that place - caps - voltage regulators.
How about a picture?

[tom66]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Try reflowing it, first...

[jettboat]

Re: Sumsung Plasma Tv PN50A550 Faulty?

I got this same model tv same fault, smps was doing same thing it tests good once it turned on. going to reflow this board later today let you know if it fixed it

[jettboat]

Re: Sumsung Plasma Tv PN50A550 Faulty?

reflow got the tv working proper again

[cliff_hootarski]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Care to elaborate your method of "reflowing" the board?

I've had several TV's I've replaced the mainboards in and I would surely like to try this "reflowing" technique before I spend any more money on mainboards.

Thanks.

[tom66]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Same technique used to repair Xbox 360 motherboards.
Seems to be surprisingly common with LCD TVs now.

[jettboat]

Re: Sumsung Plasma Tv PN50A550 Faulty?

I used a hot air gun this time, didnt heat whole board just did the ic with the heat sink & two ic to its right that look the same (customer picked it up so cant remember the location #) there are test points or little dots close to these chips to probe to see if solder is melted once molten move to another ic

[jettboat]

Re: Sumsung Plasma Tv PN50A550 Faulty?

Got this tv back worked for 2 months now back to same issue. now that I own it think going to remove the bga ic600 & the one below it these are to the left of the heat sink ic chip. If it dosent work off to moduslink for rebuild as these main boards are scarce.