Hello everyone, recently i have got iMac 820-3478-A with problem: 1 led, no power button reaction. I have started my research, and noticed, that motherboard has PP12V_S0, so it tries to start without botton pressed, but stacks at U7750 gaves no PGOOD signal.
U7750
15 pin - 3.3v
16 pin - zero volts.
18 pin - 4.77v
19, 20 pin - 5.1V
L7710 impendance - 65 ohms
I have swapped U7750, with no result. Any idea what to look at?
If i inject 3.3V in 14 pin of U7750 led 2 appears.
U7750
15 pin - 3.3v
16 pin - zero volts.
18 pin - 4.77v
19, 20 pin - 5.1V
L7710 impendance - 65 ohms
I have swapped U7750, with no result. Any idea what to look at?
If i inject 3.3V in 14 pin of U7750 led 2 appears.
