Samsung PN51D550C1F - Clicking...HELP!!!

[ptheman12345]

My Samsung PN51D550C1F just started clicking when powered on and I can't seem to figure out whats wrong. I've searched through the forum to see if anyone has came across this problem, but I've found none so far. If someone could help me find a solution to this, that would be so great Please and Thank you!

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

A good first step would bee to post pictures of the boards inside the TV so we can see what we're dealing with.

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

A good first step would bee to post pictures of the boards inside the TV so we can see what we're dealing with.

Attached are pictures of the boards

[Alastair E]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

A popular failure with these is shorted FETS on the Y-SUS board.

Worth checking the buffer for shorts too, as these can sometimes cause the Y-SUS to fail....

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

A popular failure with these is shorted FETS on the Y-SUS board.

Worth checking the buffer for shorts too, as these can sometimes cause the Y-SUS to fail....

How do I test if the Y-SUS board or buffer is bad?

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

Do you have a digital multimeter available?

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

Do you have a digital multimeter available?

Yes I do

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, see this board - top left:
https://www.badcaps.net/forum/attach...2&d=1397955423

Do not touch any exposed metal on the power board whilst AC power is connected or shortly after.

I'm assuming only basic multimeter knowledge: if you're more advanced let me know.

Plug in the TV but put it into standby. If not possible, unplug it for now and have someone plug it in when needed (later.)

The points marked VS-TP and VA-TP are of interest.

Set your multimeter to the highest volts DC range. Usually 500, 600 or 1000V. Or if your multimeter is autoranging, use the Volts DC mode. DC is marked by solid and dashed line sometimes. Do not use the AC range (marked by a squiggle.)

Place the black probe on the chassis of the TV: the metal backing of the plasma panel. This is your common/ground point.

Then touch the red probe to the VS-TP point, note reading should be near zero.

Turn on the TV. A helper is useful, you can also use the remote if it goes in and out of standby.

Note if the reading changes throughout the clicking cycle. Repeat for the VA-TP.

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, see this board - top left:
https://www.badcaps.net/forum/attach...2&d=1397955423

Do not touch any exposed metal on the power board whilst AC power is connected or shortly after.

I'm assuming only basic multimeter knowledge: if you're more advanced let me know.

Plug in the TV but put it into standby. If not possible, unplug it for now and have someone plug it in when needed (later.)

The points marked VS-TP and VA-TP are of interest.

Set your multimeter to the highest volts DC range. Usually 500, 600 or 1000V. Or if your multimeter is autoranging, use the Volts DC mode. DC is marked by solid and dashed line sometimes. Do not use the AC range (marked by a squiggle.)

Place the black probe on the chassis of the TV: the metal backing of the plasma panel. This is your common/ground point.

Then touch the red probe to the VS-TP point, note reading should be near zero.

Turn on the TV. A helper is useful, you can also use the remote if it goes in and out of standby.

Note if the reading changes throughout the clicking cycle. Repeat for the VA-TP.

When unplugged, both read to be 0.0V. During the clicking cycles, I measured VS-TP to be 1.3V and VA-TP to be 0.0V

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK. Now you see the two large left & right hand boards? Left one is Y-main, right is X-main. I want you to unplug the power connector for the Y-main (going between power board and Y-main.) Now repeat the test for VS-TP and VA-TP.

Note: Do not plug in the connector while the TV is running or within 2 minutes of switching it off. Always remove the connector with the set OFF.

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK. Now you see the two large left & right hand boards? Left one is Y-main, right is X-main. I want you to unplug the power connector for the Y-main (going between power board and Y-main.) Now repeat the test for VS-TP and VA-TP.

Note: Do not plug in the connector while the TV is running or within 2 minutes of switching it off. Always remove the connector with the set OFF.

When the Y-SUS board is unplugged, VS-TP was measured around 200V and Va-TP was measured around 58V. Both started to drop after the first click stopped

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, sounds good - probably got a bad X- or Y-main board. Plug the Y-main power back in. On the top of Y-main, find the grey connector going to X-main, unplug that, and check VS-TP and VA-TP once again.

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, sounds good - probably got a bad X- or Y-main board. Plug the Y-main power back in. On the top of Y-main, find the grey connector going to X-main, unplug that, and check VS-TP and VA-TP once again.

When the X-Main is unplugged, VS-TP was measured at 1.1V and VA-TP was measured at 0V

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, you have a bad Y-main board.

On these I would advise testing parts on the X-main but you probably do not have to replace it. We can do this later.

Please locate the LJ9x-xxxxxxx number printed on your Y-main board. NOTE: Do not use LJ4x number.
https://www.youtube.com/watch?v=R1jmj_foId0

[jwilliams1967]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

I had exactly the same problem . clicking but not switching on . Turn out to be dry joint on transistor on the power supply .the way I found it was to power on the set and very carefully push against the heatsinks with an isolated screwdriver ( heatsinks may be live ). clicking stopped and set came to life. hope this helps you .

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

OK, you have a bad Y-main board.

On these I would advise testing parts on the X-main but you probably do not have to replace it. We can do this later.

Please locate the LJ9x-xxxxxxx number printed on your Y-main board. NOTE: Do not use LJ4x number.
https://www.youtube.com/watch?v=R1jmj_foId0

I located it. Its LJ92-01764A. Should I go ahead and order the part or are there more testing that can be done to make sure its the Y-SUS thats causing the problem?

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

It's about $40 on shopjimmy.
http://www.shopjimmy.com/samsung-bn9...main-board.htm

Might be able to find it cheaper elsewhere but shopjimmy do test their boards unlike other sellers.

I think it would be prudent to remove both X- and Y-main boards and get a picture of the underside of the board, so a few quick tests can be made.

Cold joints aren't a known problem with this model and don't fit the symptoms.

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

It's about $40 on shopjimmy.
http://www.shopjimmy.com/samsung-bn9...main-board.htm

Might be able to find it cheaper elsewhere but shopjimmy do test their boards unlike other sellers.

I think it would be prudent to remove both X- and Y-main boards and get a picture of the underside of the board, so a few quick tests can be made.

Cold joints aren't a known problem with this model and don't fit the symptoms.

I'm gonna go ahead and order the part. Hopefully it works. I'll report back once the part comes in. Thanks for all your help TOM!

[tom66]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

Hang on! It's a good idea to spend 5 mins checking the X-main for faults so we don't blow up your new Y-main (it's possible for one board to kill the other.)

[ptheman12345]

Re: Samsung PN51D550C1F - Clicking...HELP!!!

Hang on! It's a good idea to spend 5 mins checking the X-main for faults so we don't blow up your new Y-main (it's possible for one board to kill the other.)

Sorry. How do I go about doing that?