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I have a iMac A1418 (emc 2833) that is not turning on The Diagnostic LED #1 Blinks when the Power Cord is plugged in and if I press the Power Button it Blinks faster. No other LEDS are on or turn on if I press the Power Button I am thinking it may be the Power Supply but not sure. Anyone have info on testing the Power Supply?
Here’s how to replace the power supply: Before doing so, pull the supply and examine the capacitors (cans) on the backside. Look for swelling and or leakage. This machine is rather new to have a failing power supply but. that’s what the diagnostic LED is telling you. iMac Intel 21.5" Retina 4K Display Power Supply Replacement
