Samsung LN46A550P3FXZA Squealing, clicking on and off

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

My three sets that I did the experiment with paralleling the caps are still working since my last post. New caps are cheap so you might as well replace it.

[valley_nomad]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

My 8+ years old LN52A550 just developed the same problem as OP's. Before reading this thread I found out that someone provides repair kit on eBay. But the seller indicates a different IC although two caps are same. So it looks like the replacement of IC may not necessary after all? Any the normal wet cap can also be used as replacement?

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

You can try 100uF 10V or 16V low ESR lytics cap in parallel with C102 to see if the problem will go away, the 3 sets I experiment with paralleling the caps are still working today.

[valley_nomad]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

Thanks. I will give it a try.
Is there a way to spot a bad tantalum polymer SMD cap?

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

You will have to remove it and test with the cap tester that can do capacitance, ESR, leakage, etc.

[amireh1]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

Hi:

Please i need help , i need to solder the 100uF 35v Cap in parallel with C102.
can i solder it on the 2 sides of the C102 cap as shown in image or i have to do it as the post of alexwitter.
also where is the positive and negative sides.
how long can i keep it and if it is fixed do i remove the faulty C102 and keep the one in parallel.

Thanks

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

White BAR of the black SMD cap is POSITIVE.
You can scrape the green solder masks from the traces to expose the bare copper so you can solder the cap's legs to that connected to the terminals of the SMD cap.

[amireh1]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

Thanks for your reply.
You think it is better to scrape the green mask instead of soldering the 2 sides of the SMD cap?
How long can i keep it in parallel?

thanks

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

There is not much exposed terminals on that cap so the cap you trying to parallel in place may come off.
The 3 sets that I added the caps in parallel for experiment are still working.

[PATM6700]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

Got lucky, all symptoms in these posts were repaired by resoldering C102 and C131. Thanks from Murf.

[kevinm34232]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

Here is the repair service for this issue on eBay

http://www.ebay.com/itm/131435134281

[Shane711]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

I tried to repair one of these boards today. I replaced both IC101 and IC102. I also replaced both Caps C102 and C131. I also added a 100uf cap to C102. Still this TV does not turn on, just clicks every 30 seconds and the light on the front keeps flashing red. www.shopjimmy.com says it is IC101 & C102 so I am guessing my new ICs are bad, I ordered them from China but I never had trouble fixing these boards when I ordered from ShopJimmy and Mouser. Well I ordered 2 New ones from Mouser today and I will update this post when they get here and I install them. I guess there is nothing else to check.

Mouser says these ICs MP2363DN are sensitive to moister, so just what does that mean? Once they are installed on the board they are going to have moisture. What purpose would it serve to bake these before installation? Does anyone have an understanding on this?

[Shane711]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

I think I understand that the MP2363DN IC has to be dry only when you are installing it. Here is a picture of the warning label on the package. It says to bake prior to installing to prevent damage. The second label says "Moisture-Sensitive Devices" "Devices require bake before mounting if humidity is too high" I am going to have to store these in a sealed container with the drying beads.

Well I installed the 2 NEW MP2363DN ICs and the board is still clicking.
I don't know what else to do. I am about to give up on this board.

[vinceroger69]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

I think I understand that the MP2363DN IC has to be dry only when you are installing it. Here is a picture of the warning label on the package. It says to bake prior to installing to prevent damage. The second label says "Moisture-Sensitive Devices" "Devices require bake before mounting if humidity is too high" I am going to have to store these in a sealed container with the drying beads.

Well I installed the 2 NEW MP2363DN ICs and the board is still clicking.
I don't know what else to do. I am about to give up on this board.

is it possible a corupt eeprom is causing this?

[Shane711]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

The EEPROM on this board appears to be a NAND and the know cause for this problem is IC101 & C102

[Shane711]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

I just got this board working. Apparently the CPU had broken solder connections. Someone suggested to me that it might be the CPU so I fluxed it up good and put my heat gun to it for 100 seconds and the TV turned on. Tomorrow I will test it with a movie after I put the heat sink and cover back on. Plus I am going to add a cooling fan to hopefully prevent this from happening again. My stress level just went down 8 notches, LOL.

[Shane711]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

OK, so after testing the TV the board only works when I warm it up so looks like the CPU is fried. Parts board. At least I located the problem and now I have more experience.

[rustytierod]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

There is not much exposed terminals on that cap so the cap you trying to parallel in place may come off.
The 3 sets that I added the caps in parallel for experiment are still working.

How are they today, if you still have them?

[budm]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

They are still running.

[rustytierod]

Re: Samsung LN46A550P3FXZA Squealing, clicking on and off

What kind of low esr cap did you use? How can I tell if these spare caps I have are low esr. I have a lot of electrolytic.