Samsung R530 white screen

[Romulo]

Hi friends I need help on this laptop Samsung R530 which giving me white screen already tried replaced the screen with good one and also the lvds cable but still the same issue display goes white.I tried on external display but no image.Anyone can help me to fix this please.thanks in advance

[Romulo]

Re: Samsung R530 white screen

anyone please help on this

[KillerFlash]

Re: Samsung R530 white screen

Try to replace your memory or clean it first,as well as the process fan heat sink.Can u still access the OS??f ever u can access it,u can uninstall the driver or disabled it, coz there is a problem on your videocard on board.

[Romulo]

Re: Samsung R530 white screen

totally white screen pressing power button display goes white and no external display. i think this is NOT a memory problem or graphics i think there is something there is missing voltage on the board.can someone help me on this please

[Romulo]

Re: Samsung R530 white screen

Anyone please help on this

[Romulo]

Re: Samsung R530 white screen

Anyone have a schematic for this model please share

[Romulo]

Re: Samsung R530 white screen

Ill tried reflowed the mosfet around the lvds connector display comes on a couple of seconds then it goes white again, so i think the problem is around here.i have attached the image and i measured voltages

board id:BREMEN-UL
REV 1.2 (100201)-4

Q502 PIN1=1V PIN2=0V PIN3=3.3V
Q504 PIN1=0V PIN2=0.6V PIN3=0V
D505 PIN1=4.6V PIN2=5V PIN3=0V
Q503 PIN1=17.9V PIN2=47V PIN3=18V

can someone please help me on this

[Romulo]

Re: Samsung R530 white screen

anyone please help

[mielta]

Re: Samsung R530 white screen

Hi
I think is the right

[piernov]

Re: Samsung R530 white screen

Remove Q504 and try again, then measure voltage on its pad (with the MOSFET still removed).

[Romulo]

Re: Samsung R530 white screen

with the Q504 removed and measured its pad PIN1=5V PIN2=3V and PIN3=0V does this mean this mosfet defective?

[piernov]

Re: Samsung R530 white screen

Those measurements are strange and I guess the pin numbering is not right.
Could you measure again the voltage on Q502 and Q504 again? Check with Q504 either removed or put back but tell us so.
Make sure you use the correct pin numbers, check on the datasheet of the MOSFET if unsure. (Q504 pins are numbered differently between the datasheet and the schematics, pin 1 and 2 are swapped)

[Romulo]

Re: Samsung R530 white screen

thanks for the response piernov sorry I was wrong measuring on the pins on Q502 i checked datasheet here is the measurement on each pin with the Q504 removed

Q502
PIN1=5V
PIN2=3.3v
pin3= 0v

[dspok]

Re: Samsung R530 white screen

Remove Q502 and jumper Pin2 and Pin3 of Q502.

[Romulo]

Re: Samsung R530 white screen

@dspok it works removed Q502 and follow you said jumper to pin2 to pin3 now it working fine no white screen anymore thank you very much for the help.same with piernov thank you!

[piernov]

Re: Samsung R530 white screen

You should still replace those MOSFET (and make sure MCH3_LCDVDDON is good) because otherwise the LCD will be powered on even when the computer is sleeping.

[Romulo]

Re: Samsung R530 white screen

ok thanks so you mean i need to replace this mosfet?if i dont replace it what should happen?what if i cannot find the same mosfet is there any replacement for this?the mosfet has a marking of XFUA, and checking Q504 mosfet now there is no voltages on each side