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"To inject 1V and 500mA to PPBUS_G3H?"
How do you think to inject exact current for an exact voltage???
The current depends by injected tension and resistance to ground on that rail
First of all, what is the exact value of that short?
Next check for any big coil with the same value.
This way you can find a shorted high-side MOSFET.
NEVER inject tension before!!!
If all MOSFETs OK, then start with 1V and go up, just maintain the current bellow the ampers limit of your bench power supply.
1V with 500mA is 1V set with 500mA as a limit for current on my power supply. It depends on the device itself, resistance on that rail, how much it will draw.
The exact value of the short is 0 Ohms.
On to the hunt for big coils with the same value then...
Always set current limit at max when inject.
The power rail in question will take the current accordingly with voltage and ressitance to ground.
This is the reason to start with low voltage, that bench power supply do not reach amps limit instantly...
If none of high-side MOSFETs for CPU is shorted, why would the current flow through the CPU???
And don't start with 3V.
If the rail tries to sink more than 5A (e.g. 3V/0.5ohm=6A), then the bench power supply will not inject at all; as it will enter in protection mode instantly.
So none of the big coils had odd values. I took a look at C7333 from the side and to my surprise, it did have a slight crack. I removed it, PPBUS_G3H measures 0.8MOhms.
Is it safe to attach the charger to see if the fans spin or shall I first replace C7333 and then connect charger?