820-4924-a ppbus_g3h 16-20v

DaltonJr.

New member
Hi,

here i have another board, that had power issue... i replaced Q7130 and U7100 and now i have 16-20v on F7140. Between pins 27/28 on U7100 there is 20 ohms resistance, too much, right? I have replaced two U7100 and the result is the same... i have also replaced c7120,c7121,c7122,r7121,r7122, but still the same. R7120 is ok. What should i check next?

Thank you
 

2informaticos

Administrator
Staff member
27/28 value is correct (020).
I bet you have bad solders un U7100 and Q7130 got burnt.
High-side part of Q7130 is shorted, no other reason for 16-20V on F7140.
This happens because of bad solders; pin24 (U7100) not soldered, leaves the Gate of that MOSFET floating on the air!
 
Top