820-3462 PP5V_S5 0.8V

[No-Clean]

Board had very little corrosion on U7201, replaced it and now PP5V_S5 is only 0.8V

Resistance on pins 17-18 and 27-28 of ISL6259 is correct
ppbus is 12.6V

U7201:1 12.6V
U7201:12 3.4V
U7201:4 3.4V
U7201:21 3.4V

Already check for shorts and all is ok.

 

[2informaticos]

"U7201:4 3.4V"
Are you sure about this?
Is really strange, if 5V_S5 is not present; means no 3V3_S5 also.

Post again basic U7201 voltages; pins 23, 12, 13, 22, 29, 21, 4.
Do you get (or not) L7260 voltage?

 

[No-Clean]

Thanks, I measured wrong, U7201:4 is 0.8V

U7201:4 0.8V
U7201:12 3.4V
U7201:13 1.3V
U7201:21 3.4V
U7201:22 5.8V
U7201:29 0.8V

No voltage on L7260

 

[2informaticos]

5.8V at VREG3???
Please post accurate information.

Where is pin 23 voltage?

 

[No-Clean]

5.8V at VREG3 yes that is correct!!

I just updated my last answer to include pin 23 voltage 12.6V

 

[2informaticos]

Then change U7201...

 

[No-Clean]

As stated in the description, U7201 was already replaced, but just in case I just replaced it again, but same measurements.

 

[2informaticos]

Check all surrounding caps and resistors.

 

[No-Clean]

Thanks @2informaticos C7203 was the culprit.