Hp da0r62mb6e1 3.3/5v problem

[NConstantinou]

Dear all

I have the above motherboard which has NB670 3v ic and NB669 for 5v.
on the pins BST I get the output 3 and 5v but the are 2 caps
PC234 and PC223, on which I get 5v but on the other side of capacitor
I get nothing. these caps are connected to 3v and 5v rail PL22 and PL24.

I have removed PL24 and measure the output of capacitor and I still get nothing.
is it the problem with IC'S!
On pin 7 on each ic I get no voltages
capacitors are ok

3.3v is ok

thanks

[mcplslg123]

Re: Hp da0r62mb6e1 3.3/5v problem

You need to fix 5V output first as 3v will come only and only if 5v line is ok as 3v ic has vcc requirement of 3v. So lets concentrate on 5v regulator. Check Pin1/7/8/12/11/13/4 for voltage and measure resistance to ground on all these pins. Most likely Pin11 is shorted to gnd.

[NConstantinou]

Re: Hp da0r62mb6e1 3.3/5v problem

Thanks for the reply

using adaptor i get the following readings on 5v ic PC10
pin1 19.5v rest 6.5Mega ohms fluctuating
pin 4 0.5v rest 4Mega ohms fluctuating
pin 7 no reading rest 32kohms
pin 8 5v rest 14.5kohms
pin 11 5v rest 196k ohms
pin 12 5.5v rest .7 megaohms
pin 13 1v rest 0.2mega ohms

[mcplslg123]

Re: Hp da0r62mb6e1 3.3/5v problem

PIn4 is HWPG AND should be 3v and pin 13 Enable is also low. The ic will have enable voltage from S5ON which in turn will come from kbc chip KB3940 PIn 101. Have you replaced the Ic PU10?? If not, try replacing it .

[NConstantinou]

Re: Hp da0r62mb6e1 3.3/5v problem

Thanks for thr peply.
i think so too that PU10 is defective.
i will order it and relace it.

i will get back to you

thanks again