Solved Is There A Way To Get A Spontaneous Boot Imac Intel 21 5 Emc 2428

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Machine would not power up, got green LED on #1 with old PSU. Just replaced PSU with one from iFixit and get the same thing. Are there any power pads to jump? Have not replaced the display yet. Apple iMac “Core i5” 2.5 21.5-Inch (Mid-2011) Specs Mid-2011 - MC309LL/A - iMac12,1 - A1311 -  2428 @danj

Try the power switch, short across the header on the logic board. To locate it jump to Step 30 iMac Intel 21.5" EMC 2428 Logic Board Replacement Update (10/28/2019) @mayer - Check the voltage on the logic board. In the upper middle you’ll find this set of pins of the power supply connection.

J600 1 PP12V_G3H 2 PP12V_S0 3 PP12V_S0 4 GND 5 GND 6 GND