mac mini a1993

[Zoli75]

Hi
I have a mac mini a1993 that is completely dead.
I checked the wires, the voltages are correct.
The u7880 (buck converter) is missing pp1v_prim. There is no short circuit on the pp1v_prim line.
Is pp1v_prim always present? Is pp1v_prim generated by u7800?

[mon2]

Re: mac mini a1993

Remove all power. Meter in resistance mode.

Check the resistance to ground of each coil on the board. Checking for a low resistance. Each coil is linked to a local power supply. Low resistance may mean you have a defective cap on the rail causing an excessive current draw and forcing the regulator to shut down.

[mon2]

For future readers / reference, yes, pp1v_prim is created by U7800.

[mon2]

Similar thread so best to continue with the active one:

Mac mini 2018 - Badcaps