Help needed locating LED fuse on Samsung NP550P7C-S05UK

[Telephonewire]

Hi all.

I have a Samsung NP550P7C-S05UK with no backlight. I have tested it with an external display which was fine.

Holding a light up to the screen I can see the display is working fine but there's just no backlight.

I rather foolishly removed / refitted the monitor cable with the battery connected. I feel so annoyed with myself and feel very sick that I now find myself in this position!

I suspect that it is a blown fuse on the motherboard but I can't locate it.

If anybody would be kind enough to offer any advice it would be very much appreciated.

Best regards,

Jeff

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Np550P7C
NP550

[khaahk]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

I think there is no schematics available for that board, post good macro pictures of LCD connector and the opposite side of the mainboard. Fuse is one possibility, embedded controller is another. If you know how to use a multimeter, then maybe it is possible to give some assistance.

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Hi Khaahk,

Thanks for your message.

I have only recently registered with the site and didn't realise that notifications were turned off by default. I have now turned them on for subscribed threads!

I have uploaded two pictures; one of the motherboard and another more detailed one of the LCD connector.

I do know how to use a multimeter! :-)

Best regards Jeff

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

There are two components in the bottom right hand corner of the circuit board where the connector is (with no markings on) that look very similar, not sure if they are fuses or resistors (or something else)?

There is another component just above then, which is horizontal, with a few letters / numbers on - is this a fuse?

There is also a component (lighter in colour) at the top of the connector - is this a capacitor?

All help gratefully received!

Jeff

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

.

[atsio]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Open the screen and post the model of your monitor

[khaahk]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Take a picture from the opposite side of the connector also. The upper (lighter) component is capacitor (probably on +19V rail), the two components down right - can be capacitors or inductors, it is hard to tell from the pictures.
The panel should get adapter power (+19V) and +3.3V, these power lines are delivered with broader vias on the pcb, that is how you can identify them. These power lines are probably switched by mosfets which are controlled most probably by EC (embedded controller).
If these voltages are present on the connector, then there are also control signals for the LCD panel itself, to turn the backlight on, and adjust the brightness. They can be found via finding the lcd panel specification and tracing the signals back to mainboard.

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Thanks Khaahk,

This is a learning experience for me!

I will take a picture of the other side of the connector and the screen and post shortly.

Could the two components down right be fuses?

Jeff

[khaahk]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

They look more like capacitors than anything else.

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Hi Khaahk,

Here is the picture of the back of the board and two pictures of the screen...

Best regards.

Jeffrey

[atsio]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Check voltage on pins 35, 36, 38, 39, 40 of the LVDS connector.

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Does anybody know where I can get hold of a schematic for the LED control board?

The screen is a B173RW01 V4

The control board is as shown in the attached photo.

Regards,

Jeffrey

[khaahk]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

specification is all you get:

atsio asked for the measurements of important pins on the panel, can you measure them?

[dspok]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

check F101 in TCON board, may be it is blown. Sometime I face such problems.

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

check F101 in TCON board, may be it is blown. Sometime I face such problems.

Many thanks for advice - I will check when I get home tonight!

[Telephonewire]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

p.s. What does TCON stand for?

[aarvi]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

hey,
this is my first post here,i also did the same mistake...
did you find a solution....???

[angel-boy]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

remove the shorted cap from picture , and change that source
and have light again

[emken]

Re: Help needed locating LED fuse on Samsung NP550P7C-S05UK

Do you have np550p7c bios guys?