Samsung PN60F5500

[usermike9]

I am working on a Samsung PN60F5500 with now power. No front panel LED and no response from the remote. The PS PN: BN44-00601A did show standby voltage. We anticipated the main board PN: BN94-06194B was defective.

I ordered both the main board & power supply just to be safe .With the boards installed I do have the standby LED on the front panel now as well as the green LED marked LED2000_L0 on the main board that blinks intermittently.

There is however NO screen illumination. I unfortunately do not have a service manual at this time. My concerns are that Samsung often has different revisions of panel and main board and the main I ordered may not match my panel? Alternately the Y-sustain PN: LJ92-01958A could also be defective.

Service manual anyone ? Ideas ?


Model: PN60F5500AFXZA

Version: US01

S/N: Z6VX3CQD600606K

Panel: S60FH-YB03


Any help would be appreciated.

[usermike9]

Re: Samsung PN60F5500

The LED on the main board is blinking every 5 seconds so if this set is the same as older ones this indicates DVR Reset . Have audio using the tuner input so it is just the panel shutdown I am fighting with now. Oh this is a pain without the service manual I am not able to locate a short anywhere on either the X or Y and the buffers are all flat pack ICs glued in so nowhere to check for shorts there besides the connectors and not sure what test points.

Last thing is this was given to me well for $20 and the history was it stopped working after a move but I don't know if it was immediately after or 1 day or 1 week etc. I have looked all over the panel for a crack and all looks good. I have removed the bezel and looked for a small crack at the edges too.

I am hoping someone here has had some experience with this set. Again the main & PS were replaced and main was bad as there was no function at all with the original main. I believe both PS are OK.

[newtothis]

Re: Samsung PN60F5500

Pics of layout of boards please

[usermike9]

Re: Samsung PN60F5500

At power on the ALL test voltages go up then drop back down.
VS - 208 then drops down
Va - 57 then drops
Ve - 8-10 it never really comes up

Y- board and buffers are out in the picture to look for any shorts or defective components on front and back side of boards

[tom66]

Re: Samsung PN60F5500

Does Vsc rise? It sounds like Ve is shorted.

[usermike9]

Re: Samsung PN60F5500

The Y-sustain was bad. Replaced it and the set came up.
My tunnel vision was from listening to the alleged history on the set. They claimed it was working A OK until it was moved and the mover damaged it...... Not physical screen damage but internal ??
The main board and Y-Sustain were both defective. Seems hard to rationalize that those died in a move. I had the bezel removed and was searching for a hair line crack near the edges . I suspect that they hoodwinked the insurance for the movers.

[usermike9]

Re: Samsung PN60F5500

Talking to myself here Set is up and working but the bottom of the screen has 3" of what looks like overscan. Anyone remember CRT bad caps in vertical section ? Lines spread out and video wrapped around ? Well that's it. It was 3" when it first came on then I ran a FIRMWARE upgrade. NO Change

So I went to service menu and did a factory RESET . Well that is when 1" of overscan and missing video at the bottom turned in to 3" ???

Well .... I have never seen this on a plasma. Analog CRT yes Plasma nooooo but ..... The parts distributor is actually saying they think it is a defective Y-sustain and want to give a refund however I just am having a hard time wraping my head around that when the factory software RESET changed the problem from 1" of distorted video to 3" . Works great otherwise but 3" missing on a 60" diagonal screen is a lot

[tw2005]

Re: Samsung PN60F5500

Talking to myself here Set is up and working but the bottom of the screen has 3" of what looks like overscan. Anyone remember CRT bad caps in vertical section ? Lines spread out and video wrapped around ? Well that's it. It was 3" when it first came on then I ran a FIRMWARE upgrade. NO Change

So I went to service menu and did a factory RESET . Well that is when 1" of overscan and missing video at the bottom turned in to 3" ???

Well .... I have never seen this on a plasma. Analog CRT yes Plasma nooooo but ..... The parts distributor is actually saying they think it is a defective Y-sustain and want to give a refund however I just am having a hard time wraping my head around that when the factory software RESET changed the problem from 1" of distorted video to 3" . Works great otherwise but 3" missing on a 60" diagonal screen is a lot

do you think it'd be worthwhile isolating the main and using the built in test pattern gen on the logic board?

I think a photo would be in order too, please

did you take note of the settings in the service menu before reset?

definitely correct main for this size or what model is set in the serv menu?

[usermike9]

Re: Samsung PN60F5500

If I understand what you are suggesting I think I have tried that. The built in Pat Gen from Service menu is the same. The Bottom is missing.

Here are the pictures of both board layout and the screen now with the missing bottom portion. Picture 3 is the best example. I just uploaded all of them. This was a batch for the parts distributor to look at. They jumped and said they thought they had sent me a dud Y-sustain. I am not convinced of that at all

And NO I did not take a B/U of menu settings. I did not change anything I just did a Factory Reset which I asssssssuuuuummmmmmeeedddd was OK well......... NOT LOL There are hundreds of sub values in there and I assumed a reset would IMPROVE things . Hmmmmm Wrong :-( Lol

[tw2005]

Re: Samsung PN60F5500

well, i'm not so sure if the tests in the main are the same as the logic. I was thinking if a change occurred after the reset then maybe take the main out of the equation, jumper the logic, remove the power connector from the main and earth the Pon to force tv on. This is from what I've read ,

[tw2005]

Re: Samsung PN60F5500

looking at that image, especially with those lines, looks sus. bad buffer, damaged ribbons , mis-seated ribbons, bad ymain, cracked solders at the ymain/buffer connector.

Not sure and not overly familiar with samsung either.

You could go into the serv menu and see though what tv model this has been set too.

may purely be coincidental the change after the reset but the main board maybe be multimodel just needs to be setup??

I'd still try logic bd test first

[tw2005]

Re: Samsung PN60F5500

does this even have a separate logic ctrl board? No manuals does make it hard.

[usermike9]

Re: Samsung PN60F5500

No manual is the hardest part. The service menu shows the correct model as well as the Samsung sticker on the board. I am considering the coincidence theory. Factory training says always always replace both buffers and Y-main together. The fact that the size of the distorted or missing part of the picture changed just after a software reset may be just something that happened after a power cycle.

Going to check and see if I can find a set of buffers I guess

[tom66]

Re: Samsung PN60F5500

Some PN60F5500 sets use a PenTile panel matrix - this has only two subpixels per pixel like some OLED displays used on smartphones.
http://www.mojmoby.pl/wp-content/uploads/2013/03/41.jpg

PenTile uses the same number of vertical lines (still 1080p vertical) but only has 3840 horizontal subpixels (compared to 5760 for true RGB 1080p.)

It is possible that if your set has the wrong firmware loaded, it would cause distortion to the displayed image.

PenTile is a way for manufacturers to reduce the display power consumption and improve brightness, sacrificing some visual fidelity, although generally not noticeable.

[usermike9]

Re: Samsung PN60F5500

Interesting theory. I am familiar with PenTile but not sure if that could cause a loss of picture at the bottom.

The more I think about it the more a defective Y-Sus or Lower buffer sounds likely . Coincidence has led me to tunnel vision more than once in the past. Assuming that the problem HAS to be software because I did see it change after that Factory Reset may be the wrong thing to do.
The set goes through a power cycle after reboot and that is when the 1" turned to 3"

I would be interested to see if there was a way to roll back the firmware or selectively install a version. The version there now was just added via the user menu in an automatic update process and now when a check for updates is performed it responds that it is up to date and no updates needed.