820-3662 Liquid

G.Beard

New member
Liquid damage. Corrosion around U7090 and U7400

Came in with no 3V42
Repaired U7090 area, repaired U7400.
No green / orange.
Replaced SMC, now have green orange.

PPBUS 12.5
3V42 is 3V42
3V3V / 5V S5 is 3V3 and 5

No PM_SLP_S5
No pulsing / cycling

PPVRTC is 3v3
CLK32_RTC is present
 

dukefawks

Administrator
ADAPTER_EN and DSW_PWRGD present? Used correct SMC from identical donor?

The SMC was probably killed by a voltage spike on 3V42 because of U7090 damage. All parts on 3V42 rail are now suspect, U1900,U1950,U5110 are the ones that will affect power on and may just as well be replaced all.
 

G.Beard

New member
ADAPTER_EN and DSW_PWRGD present? Used correct SMC from identical donor?

The SMC was probably killed by a voltage spike on 3V42 because of U7090 damage. All parts on 3V42 rail are now suspect, U1900,U1950,U5110 are the ones that will affect power on and may just as well be replaced all.

SMC, yes same board 3662
DSW present
Tried U1900,U1950,U5110

Green / Orange

No PM signals
 

dukefawks

Administrator
Checked all rails for shorts? The SMC is a good suspect again of course. Did not see answer to ADPATER_EN present.
 

G.Beard

New member
Checked all rails for shorts? The SMC is a good suspect again of course. Did not see answer to ADPATER_EN present.

Adapter enable is present.
SMC was pulled from a board with RAM failure, but I guess it could have been killed with heat but I'm not sure I've ever had that happen yet
 
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