HP ZSO50 LA-A994p rev 2.0 No power

[Jmine]

Hello Guys,

I have this motherboard that doesn't turn on. I have checked for Shorts, and 19v is present and 3.3v LDO is present on PU301 Chip. I noticed that at the jpwr1 on the 3rd pin, the voltage is 2.6V, I do not know whether it is normal or not. I don't know how to proceed from here. Please help guys!

I have attached the rev 1.0 schematics for the board. [MOD EDIT] Link to schematic - https://www.badcaps.net/forum/troubl...ed#post1044598

Thanks in advance.

[mon2]

Re: HP ZSO50 LA-A994p rev 2.0 No power

Start with PU101 charger IC.

What are the voltage readings to ground of the following?

VCC
REGN
ACDRV
ACDET
ACPRES

Post each measurement.

[Jmine]

Re: HP ZSO50 LA-A994p rev 2.0 No power

Start with PU101 charger IC.

What are the voltage readings to ground of the following?

VCC
REGN
ACDRV
ACDET
ACPRES

Post each measurement.

Hey, thanks for the reply.

At PU101

VCC : 19v
REGN: 6.1v
ACDRV: 24.8v
ACDET: 3.3v
ACPRES: 3.28v

Update: After taking measurement, I tried turning on and after trying couple of times it turned on. Strange case!

[mcplslg123]

Re: HP ZSO50 LA-A994p rev 2.0 No power

Measurement at post#3 are perfect. Look for corrosion on the board.

[silasmwirigi]

i have same machine , ACDET 2.45 , LDO 3.3 volt available but not turning on, what could be failure

[mon2]

silasmwirigi, to keep it clean, best to start a new thread with your details of your case.