820-00165 ALL_SYS_PWRDGD Low

[Instafixx]

Hello,
I have a Macbook 820-00165. Customer said it isnt turning on. When it came to me it turned on just once for sometime and the dead.
Upon inspection i found corrosion at R8159 R8158 R8151 R8152.
Replaced them. Still no success.

I checked all the Power Rails.
I am getting PM_SLP_S3_BUF_L 3.3V at R8167 but ALL_SYS_PWRGD is at 0.6V. Thought it looked fine i replaced R8167 too.

Checked from crap below Q8150 as the corrosion was below it. But nothing there too.
Macbook is drawing around 180Amps.

 

[Instafixx]

Diode Mode Measurements of Q8150

Red to Ground
Pin#7 is 7.5K Ohms
Pin#6 is 160K Ohms
Pin#5 is 15.75K Ohms
Pin#4 is 1.5M Ohms
Pin#3 is 1.1k Ohms
Pin#1 is 20.7k Ohms

 

[2informaticos]

You can test removing Q8150; is just a redundant protection.
Post voltage on all big coils.
Check diode mode to ground on the ones with missing voltage.

 

[Instafixx]

You can test removing Q8150; is just a redundant protection.
Post voltage on all big coils.
Check diode mode to ground on the ones with missing voltage.

Which Big Coils?

 

[Instafixx]

Removed Q8150. Its working fine now. Do i need to replace it ?

 

[2informaticos]

I can't see any reason to quote an entire post, visible few centimeters above.
Write directly into reply box, instead of clicking Reply button.
Please, maintain forum aesthetic.

Q8150 monitors 3 voltages.
If all these are good, then you have problems with resistor dividers connected to Q8150 inputs.
No need to bother with that circuit in such case; just leave the chip unsoldered.

 

[Instafixx]

okay. Thanks