samsung ln46a540p2fxza no power

[tom66]

Re: samsung ln46a540p2fxza no power

eserviceinfo is a good one, plus I found this one a while ago with some more useful Samsung schematics:
http://arizanotlari.com/Semalar/Tv/lcd/samsung/power/ (has a few newer ones that I haven't yet got.)

[ealequi]

Re: samsung ln46a540p2fxza no power

http://www.tgohome.com/ServiceManuals try this one. i hope that help you.Dous te bendiga.

[budm]

Re: samsung ln46a540p2fxza no power

So do you have >3v on pin 1 (PS_ON) of the 24pin of the power supply connector when you hit the power switch? You do have 5.1V STBY, correct?
CNI805 on the power supply board, pin 1 (Inverter ON/OFF), do you have >3v?

[ealequi]

Re: samsung ln46a540p2fxza no power

no i don't. I have less than 1 volt. when i try to power on it have 85 volt

[ealequi]

Re: samsung ln46a540p2fxza no power

I was trying to boost the stand by but i dont know if i should. Some time the tv turn on because i can hear the samsung music but no picture or video I check almost all the fuse and they seem to be good. some other time it just try to turn on and it go into a clicking circle. when it turn on the driver board get 81v in all test point.main boad get 85v

[selldoor]

Re: samsung ln46a540p2fxza no power

Do you have the display with all the small transformers as in the youtube video link posted by budm.

It is not much help just saying

"I have two lamp that reading are quite different"
We need to know what the readings are.

If they really are much different to the others, have you tried removing the transformers and putting the jumpers in position to fool the protection circuit, as shown in the video?

[budm]

Re: samsung ln46a540p2fxza no power

I was trying to boost the stand by but i dont know if i should. Some time the tv turn on because i can hear the samsung music but no picture or video I check almost all the fuse and they seem to be good. some other time it just try to turn on and it go into a clicking circle. when it turn on the driver board get 81v in all test point.main boad get 85v

~80v reading is telling me that you are using wrong ground point. When you work on the primary side (hot side) you have to use the negative leg of the large filter cap as a ground ref point, not the chassis. When work on the secondary side (cold side), the chassis is the ground ref. point.

[ealequi]

Re: samsung ln46a540p2fxza no power

yes, that quite similar. I tested each transformer and the reading was 81 in each, but budm tell me that i had the wrong gound so i am going to do it again. I will let you know in a minute what are the reading

[ealequi]

Re: samsung ln46a540p2fxza no power

Look that i was doing everything wrong. this is the correct reading:
cn1805
1- inv.on/off = 4.v
2-nc
3-pwm dim =0
4-gnd
5- det_5v = 5.v

on cn801 i got reading on the following pin:
ps-on = 3.v
sync = 5.v
stb = 5.v
pin 20 (gnd) 2.1dcv
pin 21-22 = 2.1v

on the driver i am only getting reading in this transformer bl121= 1.v, bl112= 1.3v, bl101= 1.3v, no reading on the rest of testing points.

[ealequi]

Re: samsung ln46a540p2fxza no power

let me clarify this.one out of three went i plug the tv i can hear the samsung music and i can see the back of the screen ligth up but even with a dvd player running i can't see no video. If i shut it off, i will has to unplug it and plug it back in order to turn it on again (if it does it)

[ealequi]

Re: samsung ln46a540p2fxza no power

Up-date. The tv is turning on and off with the remote. For how long i don't know but at least it is turning on, still no picture or sound.

[tom66]

Re: samsung ln46a540p2fxza no power

Does it make the startup sound each time you turn it on and off?

[ealequi]

Re: samsung ln46a540p2fxza no power

yes

[ealequi]

Re: samsung ln46a540p2fxza no power

I dont know much about this things but do you think it can be a probable that the problem could be on the main board and i has misslead you giving wrong reading do to my lack of experience?

[budm]

Re: samsung ln46a540p2fxza no power

So let me get this straight: you can turn the TV on, hear the SAMSUNG chime, backlights are on, but not pictures, right. So if you look at the front, you can see slight glow from the screen. If that is the case, then you need to check the voltage on the surface mounted fuse on the T-CON board to see if you have either 5v or 12v on both ends of the fuse.

[selldoor]

Re: samsung ln46a540p2fxza no power

on the driver i am only getting reading in this transformer bl121= 1.v, bl112= 1.3v, bl101= 1.3v, no reading on the rest of testing points.

I dont think we have a picture of that board? - how many transformers/bulbs?

What setting have you got your meter set on when doing this test?

[ealequi]

Re: samsung ln46a540p2fxza no power

with the tv on i check the pico fuse on the t-con board and it reading 1.8 v.

[tibimakai]

Re: samsung ln46a540p2fxza no power

...measure both ends.

[ealequi]

Re: samsung ln46a540p2fxza no power

[ealequi]

Re: samsung ln46a540p2fxza no power

ths is the board