820-01041 no boot

[Sr. Robot]

820-01041 with tiny bit of corrosion on C9081.

I thought it was the usual shorted C9081 but diode mode on PPBUS_G3H_SSD0_SNS is giving me 0.036 and resistance to ground is 80ohms

But after removing C9081 i still get 0.0036 diode mode on PPBUS_G3H_SSD0_SNS.

U9080 culprit?

 

[2informaticos]

Compare with L9080 reading.
Very likely dead NANDs; apart of U9080.

 

[Sr. Robot]

L9080 diode mode is 0.316

 

[2informaticos]

Remove U9080 and check again PPBUS_G3H; may be lucky...

 

[Sr. Robot]

Removed U9080 and still 0.030 on PPBUS_G3H_SSD0_SNS

Removed R5620 and i get 0.03 on PPBUS_G3H and 0l on PPBUS_G3H_SSD0_SNS

Removed F7000/F7001, the issue is on the side of generation

 

[2informaticos]

"the issue is on the side of generation"
Do you get the low rerading at C7050?

 

[Sr. Robot]

Sorry, i mean on the side of system. I get 12.25v on C7050

 

[2informaticos]

Check if any big coil gets the same reading.
If find it, check resistance (ohm scale) between it and PPBUS_G3H.

 

[Sr. Robot]

No voltage on big coils. Only L7030 gets 0.5v and its resistance to ppbus is 600k ohms

 

[2informaticos]

Didn't check in diode mode???

 

[Sr. Robot]

diode mode is 0.400

 

[2informaticos]

"Check if any big coil gets the same reading"
Not sure what you are doing; all coils give 0.400???

 

[Sr. Robot]

Sorry, i misunderstood the question.

The closest one is L7701 with a diode mode to ground value of 0.051. Resistance to ppbus is 90.8 ohms.

 

[2informaticos]

Then the problem doesn't come from L7701.

Did you check L9580 too?

 

[Sr. Robot]

L9580 diode mode to ground is 0.001, but resistance to ppbus is also 90ohms

 

[2informaticos]

Remove U9580 and check again diode mode on PPBUS_G3H.
Dead NANDs anyway...