820-00165 no fan spin.

[THEDUDE]

Hi, got this macbook yesterday smelled burnt wipped out the board found 2 ned av7 at C7375 and C7376 burned and broken so replaced those no fan spin. checked r5450 getting 0.8v instead of 8v not sure where to go from here hoping for some help.

ok just checked and thought i had a short on sys side of F7140 ..just injected 8v and got fan spin. bad fuse ? yup bad fuse even tho it showed continuity.

 

[2informaticos]

Do NOT do that again so fast.
If you really had a short, it could be from CPU side and fry it with 8V.
You have had luck this time.
Your problem is on the main power supply, around U7100, or Q7010.
Check first 3V42 presence.
If not, post voltage for Q7010 and D7005.
Next, check voltage for U7100, pins 2, 3, 9, 15, 19, 20.

If you injected 8V on PPBUS_G3H wihtout F7140, check now if no short on L7130 side.

 

[THEDUDE]

Thanks for the reply missed a bad fuse all working now.
I admit i was a bit fast putting power threw, but i did do it gradually.

 

[JohnB8812]

Yeah usually when the big tantalums blow, the fuse does as well. Always best to remove the fuse to inject voltage anyways. But yeah don't inject 8 volts right away.