Samsung Syncmaster 245b Plus defect?

[voodoo44]

Hi Guys,

now that there's christmas coming, it's time for me to fix my Samsung SyncMaster 245b Plus.

First of all, I started over while reading this thread:
https://www.badcaps.net/forum/showthread.php?t=15501

Same problem here with my Screen.

The monitor powers on, the blue power led comes on, but there is no image displayed. I tried this with a DVI cable and VGA cable hooked up to my computer, no dice. The only thing I did notice is that my computer can detect the monitor and knows what resolutions it supports. Also after the computer goes to standby the blue Led on the monitor starts blinking. It comes back on when I wake the computer. This suggests that the lcd motherboard is functioning properly.

After the demontation of my Screen, i wanted to check, if all the resistors are working - but then ... the powerboard seems to be another - not the same as the powerboard of the 245b(w).

Not knowing, what to do now (because the powerboard seems to have a difficult layout) I started over measuring some resistors.
I think, i have found out the 'bad guy' - it seems to be RB808, showing me only ~2.0-2.2 ohm on my multimeter (its the red one, left side on the picture).

I would like to replace this resistor, but i do not know - what should i buy?

Second question: would you have a look at my pictures, maybe you can give me a hint what parts i should look after/replace?

Regards,
Tom

[budm]

Re: Samsung Syncmaster 245b Plus defect?

What are the color bands on that resistor? That is the Source resistor for that 8-pin SMPS IC for the standby 5v power supply, it should be real low resistance like what you are seeing. Are you getting 5v standby?
By the way, you should remove all those glues before they become conductive and burn up parts and corrode the components as shown in this picture.

[selldoor]

Re: Samsung Syncmaster 245b Plus defect?

There is a diagram in this post:
https://www.badcaps.net/forum/showpo...05&postcount=1

I believe it shows rb808 as 2.2ohms

[voodoo44]

Re: Samsung Syncmaster 245b Plus defect?

Is there a proper way to remove that glue? How can i remove it without destroying the powerboard or its components?

[selldoor]

Re: Samsung Syncmaster 245b Plus defect?

Most people just soften the glue with isopropyl alcohol and gently work away at it with a plastic tool - sharpened toothbrush handle or something.

Did you check the colour bands on the resistor.