dell 5558 - 8 beeps

[lefos]

Hello everybody,

This one is acting a bit strange.
According to the troubleshooting, 8 beeps points to panel/LVDS problem - no external output
Already have checked new screen + cable.
I have tried several bios files from here and other forums with the result of no beeping but screen on external OK (attached this one also)
So I wanted your help with this one please.
Motherboard code is AAL10 LA-B843P Rev 1.0(A00) 2015-01-29.
I have attached the original file if there is something that can be fixed.

Thanks in advance!

[caspian]

Re: dell 5558 - 8 beeps

here is a link to the schematics file:
https://www.badcaps.net/forum/showpo...30&postcount=2

[dspok]

Re: dell 5558 - 8 beeps

inspect LVDS connector carefully.

[lefos]

Re: dell 5558 - 8 beeps

Hello,

Thanks for your replies. I have already inspected the LVDS connector and the place round it but I don't see anything bad. I believe there is something with the BIOS because with the one flashed it has picture on external monitor and it doesn't beep at all - connected cable or not (with the original it was beeping 8 times with no picture on external). I believe there is a difference on the files.

[caspian]

Re: dell 5558 - 8 beeps

is there back-light on the internal screen or is it completely black?

[lefos]

Re: dell 5558 - 8 beeps

It is completely black with both files.

[caspian]

Re: dell 5558 - 8 beeps

measure voltage on pin 1 and 5 of the LCD connector.

[lefos]

Re: dell 5558 - 8 beeps

Hello again,

On pin 1 it has 19V and on 5 it has 0.244

[caspian]

Re: dell 5558 - 8 beeps

now, measure voltage on all pins of U5201.

[lefos]

Re: dell 5558 - 8 beeps

U5201

pin1 : 3.1
pin2 : 0
pin3: 0.24
pin4&pin5 : 3.2

[dspok]

Re: dell 5558 - 8 beeps

U5201

pin1 : 3.1
pin2 : 0
pin3: 0.24
pin4&pin5 : 3.2

pin3 must be 3.3, change it.

[lefos]

Re: dell 5558 - 8 beeps

Hello everybody,

Today I received the part U5201 and after changing the laptop is working.
The original BIOS that I have attached is working 100% (I flashed it back to the laptop to be sure) so it might become useful for someone.
Again thanks a lot guys for the help.