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I have a Mac Pro 2013 A1481 with a suspected bad power supply, I would like to test the bus bars from the PSU to the logic board with a multimeter. Would anyone be able to provide some instructions on where to place the black (ground) probe and red probe? and what the proper voltage readings should be? Please refer to the attached photo with numbers. Much appreciated
No need for that. Your Mac Pro has Diagnostic LEDs on the I/O board. The 2nd one from the top will tell you if the PSU is supplying 11V.
