[SOLVED]820-3330 Fan spins for a second then dies and repeats. PM_SLP_S4_L

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So i have a 820-3330 board that will spin the fans for a second then turn off for a few seconds and repeat. I think it might be a dead SMC but not positive? Board has no liquid damage. Any help with thisi board would be great. Thanks

PM_SLP_S4_L - 3.3V when fan spins. 0 when not

PM_SYSRST_L - 3.3V when fan spins 0 when not - Comes from SMC
PM_PCH_SYS_PWROK - 0V all the time = SMC_DELAYED_PWRGD - 3.3V when fan spins 0 when not - Also From SMC
PM_S0_PGOOD = 0V all the time
ALL_SYS_PWRGD - 3.3V when fan spins 0 when not
PM_PCH_PWROK - 3.3V when fan spins 0 when not
PM_RSMRST_L -Always 3.3v
PM_PWRBTN_L - Always 3.3V
SMC_ADAPTER_EN - Always 3.3v

PM_PWRBTN_L - Always 3.3v - Comes from SMC
SMC_PM_G2_EN - Always 3.3v
PP3V3_S5 - Always 3.3
PP5V_S5 - Always 5v
PP3V3_S4 - 3.3 When fan spens .6 when not
PP3V3_S3 - 3.3 V when fan spins. 0 when not
PP5V_S3 - 5V when fan spins. 0 when not
PP3V3_S3 - 3.3 when fan spins 0 when not
PP3v3_S0 - 3.3V when fan spins 0 when not

SMC Power - PP1V2_S5_SMC_VDDC - 1.2V when fan spins - .9 when fan off

RTC Clock Seems fine
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Yes i do get PP5V_S3 going high for a second. But no Vcore on L7510. VVC and enable are both at U7400, But no CPUIMVP_UGATE1. Also Between L7510 and ground im only getting 1ohm. Is that normal for this board or is that to low
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Then we have a problem :(
Ask owner for any history as how this could've happened.
Are you sure there was no liquid? R7402 and 7403 ok?
No liquid at all computer is in great shape. Looks well cared for. I did some more digging and removed L7510 and found that the CPU side has a .001 voltage drop to ground and that seams way to low. :( Im thinking its a bad CPU now. Is it fine to inject 1V on the CPU line to see if its something else that may be shorted?


These CPUS have very low resistance to GND so nothing strange there.
Again, ask the owner what happened, need some clues.
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Remember as louis says "The customer never lies" Found these little fuckers after noticing the PP3V3_ENET_FET was shorted to ground preventing me from having a 25Mhz System clock. After removing them the board works. On the plus side i now have a nice oscilloscope.


Yeah it was C7737 and C7738. Not positive that it was liquid as it really didn't look to green but it was a shorted cap that killed it. But its all working now. Thanks for the help Duke!!
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