samsung hp-t5054 voltages ok no picture

[sandineyez]

hey all,
this is my thread asking for help on a specific problem. i have looked around plenty but usually a samsung np picture query results in a lot of the same results in different locations.. so here i am

i recently found this samsung at the dump. with no damage anywhere.. so i knew it was worth some effort.. heres the issue

upon initial power up the power supply clicked 3 times and didnt turn on.. so i was thrilled thinking it was an easy bad caps issue, but upon inspection i found no bad caps and realized that the set turns on after the 3 relay clicks but no picture

got into the ysus, and xsus both had good fuses and voltages were ok

Ve 63
Vs 206
Vsus -189

the buffer boards had no short circuits

if the ysus is unplugged and set is powered, the PS clicks twice and powers up, same goes for when the xsus is unplugged, 2 clicks then powers up.. if both are unplugged then the ps relay clicks once and powers up immediately.

some notes:
the chime sounds when powered up
there is no glow on the screen
the ysus does hum
the xsus does not hum
i have replaced the ysus to no avail..

how likely is it that the panel itself is at fault?
could it be the logic board?
main board?


thanks in advance

[tw2005]

Re: samsung hp-t5054 voltages ok no picture

This is commonly known as the sound, no picture scenario with Samsungs. Seriously, there are that many posts on this issue you should find some answers pretty quickly. Try searching, sound , no picture, or the part number of your ymain or go to shopjimmy, find your board and then have look at the long list of TV models and search them.

Anyway, in short you will have most likely a blown ymain and the top buffer board goes short.

The hardest and most expensive part of this is the upper buffer, the ymain can be reapired and can be as easy as locating and replacing the 88N30W fets that are dead. They're in parallel so 1 short = all short in cct, pull them out and test if shorted.

[sandineyez]

Re: samsung hp-t5054 voltages ok no picture

the ymain was replaced.. and the buffers are not shorted...

i didnt classify the failure as 'has sound no picture' bc i cannot verify the sound works on any inputs as i dont know if the internal speaker was disabled or not

the only sound i do hear is the power up chime


if the 88n30w fets were dead would i still get a Vsc voltage of -190?

[sandineyez]

Re: samsung hp-t5054 voltages ok no picture

update for future reference... it was the power supply that failed...
and after some research found that my tv was part of samsungs capacitor class action suit.

called up samsung to inquire about it and was informed that they stopped the service campaign back in February.. but they set me up with a service call anyway..

technician came over with a new smps, saying it probably wouldnt fix the problem, but alas it did..

i was kind of suprised that samsung was so willing to fix the tv even though it was out of the repair window for their campaign..

[mmartell]

Re: samsung hp-t5054 voltages ok no picture

So which voltage had failed causing it not to boot into video ?

[sandineyez]

Re: samsung hp-t5054 voltages ok no picture

the technician didnt know... nor did it...

all the voltage readings were fine once it turned on... after 3 clicks of the smps relays.

so i dont know why it didn't initialize the y and x main..


i was pleased to find out that the panel only has 6k hours use