820-0165 Fan spin about 1 sec, then off.


New member
After fan stops pulling about 24ma from the charger.

Going down the power rails I have everything till PP5V_S4RS3, on U7501 it is 5V
while fan spins, then down to zero when fan stops on pin 2. It looks like something
stops telling it to turn on. Any suggestions?


Assuming ALL_SYS_PWRGD is pulsing, which I'm betting it is, check U1950 and surrounding area. If that's clean, check everything coming and going from U6100.


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ALL_SYS_PWRGD goes to 3.3v then zero on pin 1 of U1950
PPVCC_S0_CPU on R7320 pin 2 peaks at 1.8v then zero
Both come up with fan spin, then go to zero when fan shuts off.

Just to make sure I am saying this correct, the fan spin and the voltages come
up when I connect charger, then about 1 second later the fan stops and
the 2 above voltages go to zero. At this point the voltages on the rail page above
PP5V_S4RS3 are all correct and present. Nothing changes that I have
found once the fan spin stops. If I disconnect/Reconnect the charger I get the 1 sec
fan spin then back to steady state until I disconnect the charger again. There
is no cycling or any of the voltages not present going above zero again.
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New member
No history, I wish I had stuff brought in for repair, but I am learning on
boards listed as for parts or repair on ebay so I am probably buying donor boards :).
I could find no liquids or corrosion on the board and no sign anyone had tried repairing it.


New member

When first plug in charger (These are just watching display for highest value, before went to second values)
(Did not use max/min function)

1 3.4v
2 3.4v
3 3.4v
4 0.040v
5 3.4v
6 3.4v
7 3.4v
8 3.4v

After charger plugged in 5 sec and fan spin stopped, these stay
same till you remove and reconnect charger.

1 0.003v
2 0.059v
3 0.002v
4 0.002v
5 0.007v
6 0.002v
7 0.007v
8 3.44v


New member
Checked all 22 of the resistors, they look good, checked all the pins on 6100/01
only the ones that should be ground were to ground. No visible corrosion.
Just have the traces to check left to do.

I take it this is failing when trying to load the bios?
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New member
Found bad pad and trace, ran jumper wire . The connection
between R7425 and pin 15 of U7400 was gone. Not really
corrosion but pad looked a little tarnished, scrape the black
coating off trace and copper looks like melted away.

I now have continuous fan spin, pulling about .6 amps but no chime or
display output. Back to seeing what point it fails now.
Thanks for help.