Samsung B2330H Dead

[VaNDAL_UK]

Re: Samsung B2330H Dead

Cool thanks I'll give that a go.

[budm]

Re: Samsung B2330H Dead

OK, now we to find out if it is in shutdown mode due to short circuits or the primary side of the switching power supply is not working. I will have to sit down and look at the lay out, it can be as simple as a bad start up cap.
Do you hear any fainted ticking sound from the yellow transformer?

[VaNDAL_UK]

Re: Samsung B2330H Dead

Got 0.2v on the 5v and 0.5v on the 12v

[budm]

Re: Samsung B2330H Dead

OK, now we need to find out if we have any DC voltages on the secondary (cold side) of the circuits.

[VaNDAL_UK]

Re: Samsung B2330H Dead

Large cap registors at 338V and the fuse for the inverter circuit is good.

[budm]

Re: Samsung B2330H Dead

You should have the lamps cables from lcd panel connected, no need to have the ribbon cable connected to the LCD panel

[VaNDAL_UK]

Re: Samsung B2330H Dead

Sorry I mean test it with the power supply out of the monitor (bare) nothing connected to it. As you see in the pic but with the AC connected.

I'll report within the hour.

Thanks!

[budm]

Re: Samsung B2330H Dead

No need to plug into the PC yet, the power supply should be running the minute you plug it into the outlet WITHOUT hittng the momentary power switch on the front panel.

[VaNDAL_UK]

Re: Samsung B2330H Dead

OK Thanks!

Sounds like FUN!!

Do I need to connect it up to the monitor or can I just plug the mains in on the board on its own??

I'm guessing on its own but I need to check?

[budm]

Re: Samsung B2330H Dead

OK, up to 600Vdc, that is good to use.
Set it to 600Vdc scale and take the reading on that cap's two legs, red probe to the left leg, black probe to the right leg, but please see the attached pictures first.

[VaNDAL_UK]

Re: Samsung B2330H Dead

Not very well at all. I'm a noob!

Sorry here is a proppa picture.

[budm]

Re: Samsung B2330H Dead

The AC METER function is only good for 250VAC, we are measuring DC voltage on the capacitors, from the picture, it looks like it can read up to 800VDC? Picture is not clear enough.
Please tell us how well you know how to use the meter so we can give you suggestion how to learn to use the meter.

[VaNDAL_UK]

Re: Samsung B2330H Dead

This one

[budm]

Re: Samsung B2330H Dead

What kind of meter are you using?

[VaNDAL_UK]

Re: Samsung B2330H Dead

Can't check the large cap as my meter is only rated for 250v. The AC fuse is fine.

[budm]

Re: Samsung B2330H Dead

Get the DC reading on that large cap then, you should have about 325VDC on that cap if your line voltage is 230V (230 X 1.414). I assume that you already check the main AC fuse (the red round component by the AC inlet)?

[VaNDAL_UK]

Re: Samsung B2330H Dead

I'll go as far to say no indicator lights. Not checked dc voltages or the caps.

[budm]

Re: Samsung B2330H Dead

They are OK.
So the problem right now is?
No indicator lights at all, no dc voltages on any one of the Electrolytic caps?
What DC voltage are you getting on that large blue elctrolytic cap?

[VaNDAL_UK]

Re: Samsung B2330H Dead

Readings are:
3,5 = 1324
1,7 = 810

Same for the untouched one as well

[budm]

Re: Samsung B2330H Dead

OK, PIN 5, 6, 7, and 8 are tied together as shown on the board, it just look messy that'sall. It uses full bridge setup to drive the transformer. I will post the diagram later. but mean while you need to check pin 3 (S2) and 5 (D2), and pin 1 (S1) and 7 (D1) for shorts for me first.
The small dot on the IC IS PIN 1 (TOP LEFT as shown in the picture)