820-3437 R7005 Blows out

Hi
I have 820-3437 Logic Board
As soon as I plugged charger to this Board, R7005 Blow out.
R7005 not short to Ground. I tested with New R7005 without D7005 it gives me roughly 20v on both ends. As soon I Install D7005 , R7005 blows out.
NO sign of Liquid damage on motherboard. PPBus_G3H is also not short to ground, I checkd on F7140. I removed these components C7090, C7091, C7092, U7090 after D7005 no sign of short. Could't figure out what is shorting. I replaced new chip also U7100 still didn't solved my issue. I also replaced Q7180 for no reason.
Now I need help where should I look.
Thanks in Advanced
 

2informaticos

Administrator
Staff member
"I removed these components C7090, C7091, C7092, U7090 after D7005 no sign of short. "
Did you check PPVIN_G3H_P3V42G3H voltage after all removed?

Do not expect just pure short; why didn't post diode mode on all above tested points?
We need diode mode on L7095 too.

Check all components around U7090; pay atention to C7094 and R7095/96.
 
Thanks for Help
On diode mode at L7095 no short to ground (it does not beep when I try to connect probe to ground)
Removed U7090 from Board, still new resistor blow out without it.
R7096 is about 181K
R7095 is about 360k
PPVIN_G3H_P3V42G3H is 0.65v with broken resistor and components removed.
 

2informaticos

Administrator
Staff member
"no short to ground (it does not beep "
Beep means short for you?
Multimeters beep until 060-075; is that still short for you?
On the other side, normal value on 3V42 rail is 300 aprox (diode mode I mean).
100 will not beep, but will be very bad.
These are the reasons I asked you for the real values...

"Removed U7090 from Board, still new resistor blow out without it. "
Then your problem is not on 3V42 rails.
If is not one of C7090-92, then you have a problem between copper layers, inside board.
Did you even check diode mode on that point?
 
C7090 was culprit, it was 100 ohm on diode mode and I didn't know it's bad. Sorry I didn't mention value on that Cap earlier.
Issue is solved and Board works like charm.

Thanks again for all your Help
@2informaticos 5*
 
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