820-01041 Troubleshooting damage that extends beyond the CD3215s


5v does not switch to 20v
U3200 (CD3215) gets hot (thermal imaging) regardless of port used.
Upon close inspection I discover that there is residue around ball 91 on U3200 indicating that a surge has probably taken place.

Diode checking L3200 indicates both the USB2_UPC_XB N & P are shorted.
removing L3200 only (N) is shorted to U1200. It is also shorted on the other side from the other set of CD3215's but the short stays on the U1200 side when isolated. I am sure U3200 is smoked!

My next step would be to change U3200 and U1200?

I don't have much experience with this LB and would like advice from those who have been there.



Staff member
When a CD3215 got burn with hole in, I saw damaged PCH/CPU too.
In such case, because of direct connection, overvoltage can go from 20V input untill PCH/CPU.


Staff member
You can't check all the lines corresponding to PCH, or CPU.
Can measure diode mode in the lines from PCH to CD3215 chips; but this basic check don't discard other problems.

If you have time to spend with it, remove PCH and check if low values detected disappear.
Then resolder PCH and pray nothing more important got damaged.
Well split balling a donor for U1200 went perfectly. "I was lucky"
replaced the damaged CD3215. My shorts are all gone.

Board still does not switch to 20V and the only thing glowing in thermal is the (T2)!
So unless I can change a T2 I am toast!