A2251 820-01949 No power 5V 0A

[jadao]

This one got liquid damage near U7000. It is stuck at 5V 0A on all ports.
PPBUS_G3G is missing and no short with diode mode value of 0.400.
Checked all big coils including the ssd one L9080/81 and there is no short.
I replaced U7000, checked both R7021/22 and R7061/62 and still nothing dead at 5V with no amps draw...
I removed F7000 and still PPBUS_G3H is missing on both sides.

I do get 5V on CSIN and CSIP at U7000 Aux det is ok according to the voltage divider (1.2V))
It looks like U7000 is not starting or boosting, VDDA and VDDP voltages are 0V on both sides R7075
I really don't know what i am missing I usually get 5V 0A with dead shorts witch doesn't seem to be the case here.
It may have a bad battery (waiting for a new one tomorrow), but not sure if no battery would cause 0Amp draw...

 

[2informaticos]

U7000 requires to communicate with T2, in order to generate PPBUS_G3H.

Do you get 3V3_G3H_RTC?
Did you check CHGR_RST_IN?

 

[jadao]

3V3_G3H_RTC is missing but I didn't bothered because if I am not mistaken U6903 needs PPBUS_G3H in order to generate 3V3_G3H_RTC.
Yes I checked CHGR_RST_IN it is missing because 3V3_G3H_RTC missing also.

 

[2informaticos]

"if I am not mistaken U6903 needs PPBUS_G3H in order to generate 3V3_G3H_RTC"
Yeah, big mistake...

 

[jadao]

Then I don't get it...
I see in schematic U6903 VIN1 and VIN2 inputs tied to PPVIN_G3H_P3V3G3HRTC_R and PPVIN_G3H_P3V3G3HRTC is derived from PPBUS_G3H at R5420.

 

[2informaticos]

Ooops, you're right, this is T2 machine.
ISL9240 can generate PPBUS_G3H by itself.
ISL9239 from old T1 machines can't do that.

CHGR_RST_IN with 0V is OK; we don't want active reset signal.
Check resistance (ohm scale) over C7020/23.

"VDDA and VDDP voltages are 0V on both sides R7075"
What about diode mode?

 

[jadao]

3.3 ohm over C7020 and C7023
No short on VDDA and VDDP, diode mode values 0.424, 0.423 and 4,7ohm measured on R7075

 

[2informaticos]

Check R/C7030/40 and their traces.
Replace Q7030/40, just in case.

Keep F7000 removed, until you get C7050 voltage.

 

[jadao]

It is solved!

I checked R7030/C7030/C7040 and replaced Q7030/Q7040.
I removed also ISL9240 to inspect traces underneath and I put back another ISL from a known working donnour.