Samsung BN44-00175A Not Powering Up

[flocko]

Re: Samsung BN44-00175A Not Powering Up

As you have the same error code you can check though what was told to Barn01, check all small voltages again they will only come up for a second or two but you should have long enough time to read them before they drop to 0.It may be of note that he change caps CB814/14 and CX834/35. keep us informed as you go

[Hawk2112]

Re: Samsung BN44-00175A Not Powering Up

(While Clicking)
STBY =5.195V
Vs =0.2V <-- I understand this one won't come up until this Vs_On is +5.3V
Va =65.1V
Vg =15.07V
12 =12.0V
Vamp= 18.2V
5.3V = 0.72V <-- only one out of range
Fan = 7.92V

Will pull the board back out and look closer at traces and the IC's on the heat sinks
You asked Barn01 if there where any 5 lead ICs on his and yes there are 2 on mine.
I did replace the same caps as Barn01 and then checked the remainder.

Really appreciating the help.

[flocko]

Re: Samsung BN44-00175A Not Powering Up

Hi you say you have replaced some of the caps can I ask were the replacement low ESR as general run of the mill caps will not work? if you can also back track on the ICs and get the numbers so we know what they are and how they are used, and most important if they could be part of the failed 5.3v circuit

[Barn01]

Re: Samsung BN44-00175A Not Powering Up

Check the continuity across the 5.3V trace that on the + side of the CX (I think) caps. (I don't have the board in front of me anymore). My issue was a slightly lifted trace on the cap. You can trace the 5.3V bus from the output connector cluster or 3-4 pins dedicated to 5.3V You'll see that there is one pick off going to the daughter board to measure if it's there. So go in the other direction and follow the trace around until you get to the caps in question.

[Hawk2112]

Re: Samsung BN44-00175A Not Powering Up

Damn lol.. they are GP. Will swap them out for Low Imp as soon as I can get some today.

[flocko]

Re: Samsung BN44-00175A Not Powering Up

Panasonic FM/FR/ or FC would be my preferred caps on these boards

[Hawk2112]

Re: Samsung BN44-00175A Not Powering Up

Have to order the caps (panasonic FM). Do you advise to up the Voltage to be safe as well. ie 2200uF 16V instead of 10V ?

While I am waiting I retested the pulled ones and all measured good (capacitance) but my little ESR only goes to 2 digits so read as .00.

Soldered them back in and retested. Power comes on with no error 5.3V is good and Vs comes up to 202.6 V when I pull up the VS_On (using the 500ohm)

Set has been on for an hour now and holding. I will replace the caps when they arrive but I think this one is a fix

[flocko]

Re: Samsung BN44-00175A Not Powering Up

I would just go with good low ESR caps the same voltage as were fitted, the chances are putting some heat though the cap have given them some new life, but anyway you are now up and running. sit back and enjoy Flocko

[Hawk2112]

Re: Samsung BN44-00175A Not Powering Up

Ok so it worked for a while and back to square one. I have replaced (again) CB814/14 and CX834/35 with Pan FM series caps.

voltages are
(While Clicking)
STBY =5.195V
Vs =0.2V <-- I understand this one won't come up until this Vs_On is +5.3V
Va =65.1V
Vg =15.07V
12 =12.0V
Vamp= 18.2V
5.3V = 0.72V <-- only one out of range
Fan = 7.92V

5.3V caps have continuity (Barn01 asked me to check)

Not sure what to check next.Are there schematics available for this board?

Really appreciating the help.

[ChrisLovejoy]

Re: Samsung BN44-00175A Not Powering Up

Thanks for the priceless information everybody!
Fixed my 50 inch old plasma.
I want to leave a message for the record since my error type was not described so I had to figure it out for some time.
So after about 10 years of frequent use the TV failed to turn on and the led was rapidly blinking. I isolated the power supply board and did the necessary jumps mentioned above. The board powered up and gave all the necessary voltages. But after connecting the main board the power supply did not started (no loud relay click) and rapid green alarm led constantly blinking. So at first I thought the problem is with the main board. But any way replaced the slightly bulging CB813&14 with Panasonic FR that really helped!
So if anybody has constantly blinking led without the error codes, try replacing the caps anyway despite all the good voltages.