A1466 PPBUS_Shorted

[Instafixx]

Hello,
Namaste!

I have a Macbook A1466 820-00165 with a PPBUS_G3H shorted to ground.

Removed the Fuse and i checked all the tantalum capacitors.

Found the shorted one. Removed it.
Now no Short.

Replaced the capacitor. Replaced the Fuse, but still getting only 1V on PPBUS_G3H.
I thought maybe the fuse was bad. Hence replaced it as well. But as soon as i plugged in the charger, the fuse burned.

What can be the issue here ?

[mon2]

Re: A1466 PPBUS_Shorted

If the fuse is burning, then there is an excessive current draw on the rail.

Remove the fuse and power up again. Check the voltage of ppbus_g3h to ground. Is it normal? If not, then ISL side needs to be reviewed.

Do not apply the fuse till the downside rail is with a high resistance to ground. Had the same fault last week and fault was a single shorted cap. Perhaps you have more than one on the board with a short.

Be sure the fuse you are using is the proper rating of 8A - fast blow in 1206 package.

[Instafixx]

Re: A1466 PPBUS_Shorted

If the fuse is burning, then there is an excessive current draw on the rail.

Remove the fuse and power up again. Check the voltage of ppbus_g3h to ground. Is it normal? If not, then ISL side needs to be reviewed.

Do not apply the fuse till the downside rail is with a high resistance to ground. Had the same fault last week and fault was a single shorted cap. Perhaps you have more than one on the board with a short.

Be sure the fuse you are using is the proper rating of 8A - fast blow in 1206 package.

Without the Fuse.

Voltage on Pin#2 is 0.7V
Voltage on Pin#1 in 8.6V

[mon2]

Re: A1466 PPBUS_Shorted

Measure the resistance to ground on pin # 2 (no fuse installed).

[Instafixx]

Re: A1466 PPBUS_Shorted

Measure the resistance to ground on pin # 2 (no fuse installed).

Diode Mode Reading of Pin#2 (Meter Set to 2k Scale)
Red to Ground .423
Black to Ground 1.302 .

[Instafixx]

Re: A1466 PPBUS_Shorted

Found another Capacitor Shorted. Replaced. Resolved