820-3662 charred points on dcin board short on PPBUS_G3H

grmacs

Member
2 is now 16.25V
17 is now 2.3V
other readings remain same:
1-3.6mv
3-.477V
9-0V
12-3.42V
13-3.39V
14-3.26V
15-48mV
19-5.53V
20-5.53V
27-16.2V
 

grmacs

Member
Replaced ISL and now get 3.9V at pin 3. PPBUS_g3H is now 12.6-13.6V not stable.
Still no fan spin on charger only.
 

2informaticos

Administrator
Staff member
PPBUS_G3H must be steady 12.6V, without battery connected.
3V42_G3H is stable?
Do you get 3V3_S5?
Be sure to use original 60/85W Magsafe 2 charger; check PM_BATLOW_L.
 

grmacs

Member
See responses below...

3V42_G3H is stable? yes 3.43V

Do you get 3V3_S5? yes, steady 3.35V

Be sure to use original 60/85W Magsafe 2 charger;

yes using original 85w charger

check PM_BATLOW_L. = 3.34V
 

2informaticos

Administrator
Staff member
That's no good.
Remove F7140/41 and check C7140 voltage; keep battery disconnected.
Resolder U7100 and surrounding components.
 

grmacs

Member
resoldering u7100 did it. Found out the short to display was actually the connector so it killed the display and a chunk or short was in the connector also so this was a big job for me as I'm new to this but I successfully put a new lvds on the board and it is ready for pickup for the customer.

Thanks for your help!
 
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