Samsung PS-42C96HD DEAD

[Ahakim]

I'm working on a SAMSUNG PS-42C96HD:
TV dead! Not even a standby voltage!
POWER BOARD:
VDD on pin4 of VIPer22A (SMPS primary switcher) is ZERO vollt(s). In fact ZDB803 is short (overheated I guess!?)

Help needed:
-- value of Zener ZDB803
-- typical value of VDD
-- service manual of this TVC...(at least the SMPS cicuit:..)
-- What could be the original cause of this short??

Thanks a lot...

[tw2005]

Re: Samsung PS-42C96HD DEAD

What's the PSU part number?

[tom66]

Re: Samsung PS-42C96HD DEAD

BN44-00161A part #?

[tw2005]

Re: Samsung PS-42C96HD DEAD

1N5425B , 15V 1/2W zener

I'm thinking Tom's number will be correct, so here's a schematic. I think it covers 42 and 50"

[Ahakim]

Re: Samsung PS-42C96HD DEAD

Thanks guys...the problem is solved:
Indeed the ZENER must be a "15 to 30" volts. the ref. on the diode is gone(from heat).
(although the schematic is not exactly the same)
The one in the attached file (special thanks to tw2005) indicates 2 15V ZENERS 1N5245B in series, while in the TV I'm working on there is only one.(I think this could be annother factor of overheat):
I put 2 10V zeners in series and everything is OKKK. The TV became ALIVE again. With these 2 ZENERS in series: no more overheat & I got exactly 17.4 V on PIN 4 of VIPer22A. That should be OK. 5.1v for sdby is back again ...TV works perfectly.
Also RB830 is 1ohm 1/2 w not 2.2 as in the schematic.

[tw2005]

Re: Samsung PS-42C96HD DEAD

Probably why the part number for PSU would be handy to locate the right schematic if it's out there.

[Ahakim]

Re: Samsung PS-42C96HD DEAD

Yes you're right...In fact I wrote all the info. of the power board on a sheet of paper...I closed the TV ... I left the sheet in my workshop...I'm now dead tired at home...
That will be for TOMORRROW...
Thanks anyway.

[Ahakim]

Re: Samsung PS-42C96HD DEAD

This is all the info. I can read on the back cover of the 42" SAMSUNG TV (I mentioned earlier):

PLASMA DISPLAY
Model: PS-42C96HD
Model code: PS42C96HDX/XEC
Type No.: CA42C9
AC 220-240V 60Hz 380W
Manufactured: January 2008
Made in SLOVAKIA

As for the PSU part ref:

DYP-42W2 PLUS
Rev 1.0
Code: BN44-00194A
Input: 200-240VAC
50/60HZ 480W

Now if you can help find the schematic of this power supply unit, I would be very thankful. Although the tv is repared, I would like know the exact value of the Zerner that caused the problem, & keep a copy for future ref. Thanks.

[tom66]

Re: Samsung PS-42C96HD DEAD

Top result
http://www.tgohome.com/ServiceManual...&Search=Submit

[Ahakim]

Re: Samsung PS-42C96HD DEAD

OK OK ...
Thanks so much TOM66!! It's a library...

[philip10001]

Re: Samsung PS-42C96HD DEAD

hello this is my first post , i have just inherited one of these sets and i am having problems .

No sound . no vision.

after power is connected blue light on front power switch solid then when pressed flashes four times then goes out.

Powerboard outputting respectable voltages without x and y boards connected.

Re-connect x and y boards power on Vs dissappears to zero Va still present at 6ovdc.

Disconnect x board with just y board connected then power on Vs is there at about 201 vdc.

Any ideas , I suspect x -board is poorly.

[ReeceyBurger123]

Re: Samsung PS-42C96HD DEAD

Xsus is dead then

[philip10001]

Re: Samsung PS-42C96HD DEAD

Xsus is dead then

I thought so , many thanks . I have another board on the way.

[syaoran123]

Re: Samsung PS-42C96HD DEAD

before you swap the x-sus, did you do any tests?
how about the y-sus? have u checked if there's a short between Vs and GND on connector CN5004. also check transistors Q5001 and Q5007.

[philip10001]

Re: Samsung PS-42C96HD DEAD

Ok latest update on the situation , new board arrived fitted turned on TV.

Had sound still no vision shut down tv went for some food came back turned on no Power!!!
No click from power board . Vs and value were always low thought it was my meter not being accurate enough Vs was 199/200 Va 60 / 61. Also will check those points mentioned in above post . Thanks.