For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
820-000165 with no liquid damage wont turn on. All power rails good up to P3V3S3 which is only 0.12V checked for shorts on both rails are not shorted. I see PM_SLP_S4_L is responsible for P3V3S3 I have 0V on PM_SLP_S4_L but no shorts on either rail.
When checking pin 9 of U7100 noticed it was worked on before and was only getting 0.34V so changed ISL but in process the board made a snap noise and I now have a short on PPBUS_G3H. With all caps and ISL removed the short still remains. Is this a internal short at this point from using to much heat?
with F1740 starts at 0.10ohm and continuous climes to a higher number 1 by 1 every few seconds
without 0.395
checked everything with F7140 removed and short doesn't appear anywhere anymore. As soon as F1740 is back on o.10ohm and climbing returns. Tried different fuse but same result
If you really have short on PPBUS_G3H, it MUST be present in one pad of F7140, once removed...
Disconnect charger and battery, when check diode mode, or ohm scale...
F7140 has two pads.
So if removed, you MUST get two different readings; for each pad.
And you should get higher values without fuse; this depends by measuring pad too.
You do something wrong.
Cannot get lower reading without the fuse.
However, 135 (diode mode) is correct value.
No need to remove fuse then.
All I told to do is because you wrongly assumed a short there.
Be sure ISL6259 is properly soldered and post some voltages; 1, 2, 3, 9, 12, 13, 14, 17, 19, 20, 27.
Pin 3 had a short so replaced ISL6259 and afterwards was 0.10V on pin 3 but 5V on pad one on R7110 R7111 and C7111 for a short bit and now 0V again and short returned.
This is the 3rd ISL 6259 I have replaced on this board now.
replaced ISL6259 once again now 4.87V on R7110 R7111 and C7111 but only 0.15V on the actual pin 3 of the ISL. My soldering is fine and traces look fine, no liquid damage on this board.
Please, specify where the short is; and post the ohm value.
You must get aprox 4V on ACIN pin of U7100.
Check the trace from pin3 to R7110/11; with multimeter, not the eye!