A1990 - 820-01041 no power

Hi,

I have an A1990 820-01041 with no power.

It only has 5V on ampmeter and 0.01A

All CD3215 LDO and CC1/2 diode readings are normal and no big coil is shorted (includind SSD's).

PPBUS_G3H is shorted, with 0.003 in diode reading. Already removed F7000/1 and U9080 and the short remained.

I've injected 2V and have an 1A consume, but I cant see anything hot in the IR cam with the heatsink removed.

Can you help?

If no short on big coils (including SSD), then is safe to inject higher voltage.
Increase step by step, using a good thermal camera.

TKS. It was a burnt cap.

PPBUS_G3H is no longer shorted, and the mac now powers on again.

Howver, it has a strange power behavier: some times charges, and than stops charging and keeps doing that forever.

When this appneds, it drops the voltage from 20V to 14V to 5V to 0V to 20V... but not always exactly like that.

Any idea on how should I aprouch this problem?

Did you test with known good battery?