Samsung PN43D440A5D won't turn on

[caji1941]

I have a Samsung PN43D440A5D that won't turn on. I have not touch this TV for a year now. When I plug it in I can hear clicking sound on the back then it stop. Red light at the left hand corner is constantly on. The remote control is not functioning even with a new battery.

I am thinking of replacing the power supply board. Some of the suggestions on this forum is to replace both X & Y boards. Any suggestions? I have not looked into the cost of X & Y boards but the power supply is only $20.00.
Hope to hear from you soon guys.

[tom66]

Re: Samsung PN43D440A5D won't turn on

Can you supply some photos of the boards in your TV? There are at least two different versions of this set with different X-main boards.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

^ as tom stated, also a quick test to see if the panel fires up (no picture) is to remove the power plug from the Xmain and turn on the TV and see if you get the Samsung power on chime or a steady power LED light if the chime was turned off.


I just did a A2D not to long ago, the Xmain's are pretty spendy you are looking at 75-110. You will also need to upgrade the firmware ASAP as soon as you get it up and running with a picture. http://www.samsung.com/us/support/ow...ct/PN43D440A5D

Also be warned, these are fragile beasts and when the Xmain goes it has a chance to take out the Y-main too, I got lucky with mine and the Xmain was the only piece that I replaced due to all the SMD fets being toast and I got working Xmain out of a working/bad panel unit.

good luck! also if you replace a board make sure to set your VA/VS voltages to spec again to keep the voltages up to par

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Thank you all for responding quickly. My X board does not have connection to the power supply. It has ribbon connection to Y board and the main board. I have a hard time attaching pictures to this reply. I will try again later.

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Tom , here's the pictures of the back of the TV. Sorry the first picture is wrong. The second picture shows the X board and the main board. I will send you the right picture.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

Your Xmain power connector runs off your Ysus board.

I have mine apart now readjusting some voltages.

Our panels share the same Xmain board and probably others too

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Here's the right picture.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

Just like mine, disconnect the top most connecter on the Xmain and plug the panel back in and turn it on and see what happens.

Question, are you getting any audio output in any input in your current state?

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Shinju- I disconnected the X board from Y board. I use the remote to turn on the TV and I heard the Samsung power on sound and the led on lower left is gone. Looking at the back the control board green light blinks every so often. What does this mean? What board should I replaced.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

Xmain is shot, get some va/vs and Vscn voltage readings while the Xmain is disconnected.

You will see test points on the ps for VS/VA and VSCN is located on the Ysus below the transformer.

Just get readings DO NOTA ADJUST any pot yet.

See if your vs/va match the sticker on the panel.

[caji1941]

Re: Samsung PN43D440A5D won't turn on

With the X board connected: VS-0.1 mv, VA-0.2mv,VSCAN-3.8mv Using RadioShack digital multimeter.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

Post a picture of your DMM?

Put your meter to VDC 600 or the highest it can go.

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Here's a picture of my old tester. The max range for VDC is 1000 and the AC range is 750VAC.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

Not familiar with it, set it to VDC and get voltages.

What does the panel sticker tell you?

[caji1941]

Re: Samsung PN43D440A5D won't turn on

If I can't get any reading from the test point of the power supply then there is something wrong with this board. The panel sticker indicates Vs-207, Va-58 and Vac-185. I found a power supply for a different model no. will it work if it is exactly the same configuration? The circuit board no. is the same.

[Shinju]

Re: Samsung PN43D440A5D won't turn on

2010/2011 models
Will not be run with the “X” or “Y” main disconnected. The SMPS will shut down immediately. However if a meter is first connected to the test point when power is applied it will read the correct voltage briefly before shut- ting down.(You have enough time to check key voltages).

Sorry, just verified this with mine too. So many panels lol they all start to blend together

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Thanks for staying with me on this. I am determined to fix this TV even if I have to replace all the boards. With the X-main disconnected, I will measure again all the voltages Va,Vs, & Vcan at the instant the power is turned on. I noticed the last time I measured, it is diminishing in value.

I will give you the result sometimes today. In the meantime I will be looking for X-sus board on Ebay.

Have a nice day!!!

[tom66]

Re: Samsung PN43D440A5D won't turn on

These X-main boards are easy to repair - a few IGBTs and a driver IC. Some basic surface mount soldering. Check the Y-main for shorted IGBTs too as it's possible for the X-main to kill it.

[caji1941]

Re: Samsung PN43D440A5D won't turn on

Thanks Tom. I don't know what IGBT means. I know what IC means Integrated Circuit. Should I decide to repair the board, where can I buy the parts.

[tom66]

Re: Samsung PN43D440A5D won't turn on

Parts are available from ShopJimmy, eBay and others.

Can you do surface mount work? Have you ever done a fine pitch SOIC chip before?

You will need a good soldering iron (temperature regulated)