Power-cycling 820-3332

bjf

Member
This was submitted as a liquid-damaged board although I'm not seeing any signs of it. I've attached pre-cleaning pics. It's cycling 5V_S4 along with 5V_S0, ALL_SYS_PWRGD and every other voltage I can think to measure every few seconds. Nothing on Vcore. Vcore is measuring a short of 0.001 (1.1Ω) Is it more hopeful with a Vcore short if PPVIN_S5_HS_COMPUTING_ISNS wasn't shorted? (so the CPU didn't necessarily get hit with 12V) Either way, any tips for how to progress with this?
 

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dukefawks

Administrator
Vcore resistance is pretty low on these boards so that seems ok.
If ALL_SYS is pulsing too and Vcore is not doing anything I can already tell you this one will suck. Did you check around U7400, R7402/03?
 

bjf

Member
U7400 is getting power. The area is completely clean. Do you know what voltage I should be getting on pin 1 of R7402 and R7403?
 

dukefawks

Administrator
Can't say unless the system was working. Measure the actual value and inspect for corrosion.
Power cycling can be anything, from crap under chips to one small knocked off resistor....
 
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