00165 low 3v42

[grmacs]

Board isn't necessarily clean but no liquid contact or relevant visible corrosion. PP3V42 is usually either 1.5V or 2.2V with no correlation to anything I can tell.

Board is on bench and checked with Main flex cable removed also and tried with different DCIN board.

Things I tried: replacing U7090
Pulled U7100, U1900, U5110, SMC. Thoroughly inspected areas with direct pp3V42 connection. NO change in PP3V42 with any of those components removed.

Also get 1.2V on PP1v2_VDDC_SMC_S5

Replaced L7095 also.

Checked with FLIR also... not seeing anything unusual but suspect this is not major short. I get .313 in diode mode on pp3V42

 

[2informaticos]

Remove C7095 and test.
Check R7095/96 integrity and traces.
Post diode mode to ground at L7095.
Play with Ra/Rb to get correct voltage.

 

[grmacs]

Voltage dropped? to 1.2V with C7095 removed but guessing that didn't cause the drop. Regardless, no pp3v42 present still.
Diode at L7095 is .313.
What do you mean Ra/Rb to get correct voltage?

 

[2informaticos]

Look at the formula near that area in schematic.
Ra and Rb are clearly marked.