I have an 820-00923 that ive been working on. the top side is covered in corrosion from a liquid spill. Started out only getting 5v from the charger, there was a burned trace between the test point and the enable pin to enable pp3v3_g3h, ran a wire got that working. getting 20v from charger, had a short to ground between ppbus_g3h to pp5vs4 through the lifeboat connecter, and a couple caps on the ppbus line were shorted to ground. removed the connector and the offending caps, and was getting 13v on ppbus and was getting s5 rails. pp5vs4 was shorting to ground via the pmic so i removed it. now all of the sudden i have a direct short to ground on ppbus. I injected voltage but the only thing getting hot is the ground clip i clipped to the board. i am completely lost as to where this short is. Ive dumped alcohol all over this board and cant see anything getting hot but that clip. it draws over an amp at half a volt so something should be burning up. Am i missing something here? any help is greatly appreciated
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Absolute mess of an 820-00923 direct short on ppbus_g3h
- Thread starter Gannons3
- Start date
So got 13V and now short there?
Before injecting voltage, why didn't read how to do it?
Many times explained on the forum...
Compare exact ohm value with all big coils, especially ones from CPU.
You can detect shorted high-side MOSFET in this way.
After remove it, then is safe to inject higher voltage.
Before injecting voltage, why didn't read how to do it?
Many times explained on the forum...
Compare exact ohm value with all big coils, especially ones from CPU.
You can detect shorted high-side MOSFET in this way.
After remove it, then is safe to inject higher voltage.