820-00138 no power no green light

[techgeeksna]

Good Day, got a 820-00138 board, has history of water damage, board was cleaned off, not getting a green light and no power. what will i need to check?
there is no pp3v42
and pp20v_dcin_fuse - 16.7V
adapter sense 0V

 

[techgeeksna]

UPDATE:

DIODE MODE U7100
PIN17/18 - 3.4 Ohms
PIN27/28 - 20,9 Ohms

Voltages on U7100
2 - 16.5V
3- 3.8V
19-5.54V
20 - 5.54V
1 - 0.01V
26- 14.32V
9 - 0.02V
15- 0V

 

[Gurmon]

Lets start with restoring 3.42v rail. Have you checked for any shorts on this line ?

Diode mode measurement on L7090
Voltage on R7020 ?

 

[techgeeksna]

Hi are you dure about L7090, doesnt seem the be on this board
R7020 Pin 1 16.7V and Pin 2 0.27V. Looks corroded so ill replace that now.

 

[techgeeksna]

Gurmon Great News replaced R7020 and machine fired right up . everything seems to be working as should however the machine does appear to be running rather slugish. Has anyone come across such an issue after water damage.

 

[JohnB8812]

Run internal diagnostics and see if anything fails. Could be a bad battery

 

[Gurmon]

Good news, i meant L7095......long day.

 

[dukefawks]

Run diagnostic to see if any errors appear. Make sure battery is working and charging.