820-3787 Cycling

bjf

Member
Can't figure this one out. CPU power is going up to normal every time. Y1905 voltage is also going up to normal every cycle. ALL_SYS_PWRGD cycling to normal too. All voltages cycle up to normal. U1950 is good. Board was barely hit by liquid. I attached pre-cleaning pics. Not much there at all. No shorts that I have found. Vcore is at 14Ω to ground. Checked all SPI resistors and traces. Not sure where to look next.
 

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bjf

Member
There is barely any sign it was spilled on. The only thing I could find was on the 5V_S4 line on J9510 and C9511. Measuring fine though. I was concerned U5823 might have been hit but it looks good and the voltages are measuring normally also. All the voltages cycle every 3 seconds or so and it's just an up and then right back down thing, so maybe 1 second at most.
 

dukefawks

Administrator
Yeah this one will suck. All I can say is inspect closer for corrosion. CPU may have died as is so common on these.
 
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