Repair of BIOSTAR A78LMZ motherboard without running code

BIOSTAR A78LMZ motherboard does not run out of code, after replacing q106, the fault is repaired.

Machine model: BIOSTAR A78LMZ

Fault phenomenon: motherboard does not run out of code

Repair of BIOSTAR A78LMZ motherboard without running code Figure 1.

Maintenance process: get the machine, customer response no booting.On the diagnostic card test machine, found that switch, but not run code.No CPU VCC was measured, so Xinzhizao Soft software was used to check the drawing, and it was found that the 36 pin of U8 was not opened.

Repair of BIOSTAR A78LMZ motherboard without running code Figure 2.

Repair of BIOSTAR A78LMZ motherboard without running code Figure 3.

Only the drawing has no point and can only start running.Find q68, measure the B of q68 is extremely high, the problem is in the front, and then run the line to find that Q69 B and C are all high. It seems that the problem is still ahead, it is q106 problem.

Repair of BIOSTAR A78LMZ motherboard without running code Figure 4.

Repair of BIOSTAR A78LMZ motherboard without running code Figure 5.

Find q106, measure C pole has 0.2 or so,VCC,multimeter just removed, heard a drop.Find a Parts motherboard, change q106 happy running code, maintenance is over.