Sceptre X9G NagaV - does not power on

[Freezer]

The patient is a Sceptre X9G NagaV monitor that does not power on. This monitor is a 19" flat panel with CCFL back lighting. It has both DVI and VGA inputs. Before even opening the monitor I suspect bad caps on the power board.

After opening the back off the monitor I was surprised to see the layout. Instead of a video board on the right side, the DVI and VGA connectors were cables running to the video board under a metal plate. Just a different design from the typical.

Focusing on the power/inverter board, I immediately see two bulging caps. The bulging caps were 1000uF/16V. Even though I have an ESR meter, I decided to just replace all caps on the power/inverter board. The full list of caps on the power/inverter board:

1000uF/16V (2x)
470uF/35V (2x)
220uF/25V (5x)
10uF/50V (1x)

I replaced all the caps with Panasonic FM and FC series caps. The board was very easy to work with. Desoldering the caps was very easy. After replacing the caps and putting the monitor back together it powers up just fine.

[tom66]

Re: Sceptre X9G NagaV - does not power on

It looks like the T-con and main board have been integrated into one single board, which is bonded to the LCD, making it non-replaceable and difficult to repair.

[jetadm123]

Re: Sceptre X9G NagaV - does not power on

If you can remove the metal cover/plate, it might show the mainboard as a separate board.

[budm]

Re: Sceptre X9G NagaV - does not power on

oops.

[tmon]

Re: Sceptre X9G NagaV - does not power on

Caps on this one look good, and other suggestions?

[sirswears]

Re: Sceptre X9G NagaV - does not power on

so i have a similar problem i removed the two 1000 microfarad caps from the top right section and im going to replace them soon but my board appears to have had an additional red ceramic capacitor with a pink resistor right next to it near the two common mode choke coils does anyone know the appropriate vales are this info would be much appreciated

[selldoor]

Re: Sceptre X9G NagaV - does not power on

Pictures?

[sirswears]

Re: Sceptre X9G NagaV - does not power on

here is an update on my issue this discussion mentions my problem as well

https://www.badcaps.net/forum/showthread.php?t=7523

i'm missing the Red ceramic capacitor and the pink resistor at C65 and R88
they've blown clean off




http://www.ebay.com/itm/SCEPTRE-X9G-...-/121338172825

this is what it's suppose to look like

[budm]

Re: Sceptre X9G NagaV - does not power on

Can we see good clear pictures of the bottom side of the board so we can determine the functions of those two components?

[sirswears]

Re: Sceptre X9G NagaV - does not power on

I'm sorry i was lucky to get the pics i did what about the pic from the ebay link does that work OK

[budm]

Re: Sceptre X9G NagaV - does not power on

I just need to see the bottom side so I can trace out the connections.
This is what I can do if I have good pictures:
https://www.badcaps.net/forum/showpo...9&postcount=12

[sirswears]

Re: Sceptre X9G NagaV - does not power on

I can't get it right now i don't have access to a good enough camera but i'm sure i can get the pictures by tomorrow

[sirswears]

Re: Sceptre X9G NagaV - does not power on

this is what i can do for now i'll try better later if you need it

[budm]

Re: Sceptre X9G NagaV - does not power on

Please take the straight shot of the board in that area where the cap and the resistor are, and please make sure it is in focus.
So far the cap and the resistor look like they are for the RC snubber network for the power MOSFET that drives the power transformer. You will need to check that MOSFET to see if it is damaged or not.

[selldoor]

Re: Sceptre X9G NagaV - does not power on

Stumbled across this - dont think its relevant to current discussion and may of course vary from board to board but may help someone sometime.
IP-BOARD MODEL: HOAU462001 REV. 1.2

C5 / C12 = 1000uFx16V

C6 = 220uFx25V substituir por 1000uFx16V ********

C11 / C13 = 470uFx35V

Q1 = 2SK2996

Q11 / Q13 = AOD408 (MOSFET Canal N)

Q10 / Q12 = AOD405 (MOSFET Canal P)

U1 = SG6841 (Green-mode PWM Controller)

U2 / U3 = KA431

U6 = BIT3193G

T2 = Transtek TMS91205CT
-------------------------------

******** no idea what that means but doesnt sound like a good idea

[sirswears]

Re: Sceptre X9G NagaV - does not power on

these looked good on the phone i used hopefully they look ok to use how do you get the zoom in functionality on this forum

[budm]

Re: Sceptre X9G NagaV - does not power on

OK, it is for sure the RCD are the snubber network, the problem now is to find out the value of those two components.
So the burnt parts are completely destroyed? I expect the resistor to be in 100K or more, and the cap to be around 200~1500pf range, see example circuit.
But at this point you need to check the resistance between:
G & S
G & D
D & S

[sirswears]

Re: Sceptre X9G NagaV - does not power on

ya the resistor and the cap are gone i read somewhere they like to either burn up completely or explode i found nothing resembling them at all when i first opened the monitor

[selldoor]

Re: Sceptre X9G NagaV - does not power on

Ok so if some monitors dont have these and work maybe yours should still work
without them?
Have you done any other tests? eg if you just plug in the power supply do you
get any voltage on the BIG cap. - Test with care meter on 600vdc.

[sirswears]

Re: Sceptre X9G NagaV - does not power on

well generally if there are differences in power/main boards in the same model of monitor it's for a good reason i'd put money on a board without the two items i need not working with my monitor also i still need to find apropriate replacements for the two 1000uf 16 volt capacitors if anyone has suggestions it would be much appreciated also budm how do i test those points i don't know if i even have the right kind of volt meter mine doesn't measure microfarads