Guys, my iMac turned off and doesn't want to turn on again, I realized it was very hot, I even thought it could be some overheating protection, but after hours of turning it off it won't turn on, I notice that when the plug is plugged in, a green LED lights up, but Even pressing the power button it doesn't turn on.
=== Update (12/12/23) ===
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[image|3175412]
I decided to test the power supply with a multimeter, using this Apple manual as a reference.
Pin 3 is not supplying voltage.
Pin 4 is supplying 12v, as Led 1 is on when the AC cable is connected.
Pin 11 starts supplying 12V after pressing the power button. It corresponds to LED 2, but LED 2 does not light up after pressing the power button and the iMac does not turn on.
Pin 12 starts to supply 12V after pressing the power button.
=== Update (12/13/23) ===
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[image|3175853]
Guys, I was using the incorrect technical manual, I found the one for the iMac 21.5 Late 2009 and did the voltage test using the pins on the logic board.
-Pin 4 has 12v when I connect the AC cable and LED 1 lights up.
-Pin 11 is at 0v when the iMac is off. When I press the power button it goes to 12v, but LED 2 doesn't light up and the computer doesn't turn on.
-Pin 12 is at 4.6v, when I press the power button, it drops to 0v.
=== Update (12/13/23) ===
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I decided to take photos of the source for you to analyze, something caught my attention, this component looks strange, with these stains.
[image|3176427]
[image|3176437]
[image|3176428]
[image|3176429]
[image|3176430]
[image|3176431]
[image|3176423]
[image|3176424]
[image|3176425]
***UPDATE***
I decided to record a video showing the test I did with the font, please forgive my bad English.
https://youtu.be/izNx60SKduI
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=== Atualizar (12/15/23) ===
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@oldturkey03 @Dan Guys, I tested the new power supply, it didn't solve the problem.
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So I decided to remove the logic board and visually analyze it, I found this burnt mark that is in the photo, close to the CPU.
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[image|3178018]
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Now I'm in doubt because of the following: I have two options. Buying a logic board (I also need to buy new fans) In total I would spend US$131. Or buy a 2011 iMac 27" that has a GPU problem, the iMac would cost US$202.36 + US$51 for the GPU = US$253.36
Guys, my iMac turned off and doesn't want to turn on again, I realized it was very hot, I even thought it could be some overheating protection, but after hours of turning it off it won't turn on, I notice that when the plug is plugged in, a green LED lights up, but Even pressing the power button it doesn't turn on.
=== Update (12/12/23) ===
[image|3175412]
I decided to test the power supply with a multimeter, using this Apple manual as a reference.
Pin 3 is not supplying voltage.
Pin 4 is supplying 12v, as Led 1 is on when the AC cable is connected.
Pin 11 starts supplying 12V after pressing the power button. It corresponds to LED 2, but LED 2 does not light up after pressing the power button and the iMac does not turn on.
Pin 12 starts to supply 12V after pressing the power button.
=== Update (12/13/23) ===
[image|3175853]
Guys, I was using the incorrect technical manual, I found the one for the iMac 21.5 Late 2009 and did the voltage test using the pins on the logic board.
-Pin 4 has 12v when I connect the AC cable and LED 1 lights up.
-Pin 11 is at 0v when the iMac is off. When I press the power button it goes to 12v, but LED 2 doesn't light up and the computer doesn't turn on.
-Pin 12 is at 4.6v, when I press the power button, it drops to 0v.
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=== Update (12/13/23) ===
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I decided to take photos of the source for you to analyze, something caught my attention, this component looks strange, with these stains.
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[image|3176427]
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[image|3176437]
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[image|3176428]
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[image|3176429]
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[image|3176430]
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[image|3176431]
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[image|3176423]
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[image|3176424]
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[image|3176425]
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***UPDATE***
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I decided to record a video showing the test I did with the font, please forgive my bad English.
Guys, my iMac turned off and doesn't want to turn on again, I realized it was very hot, I even thought it could be some overheating protection, but after hours of turning it off it won't turn on, I notice that when the plug is plugged in, a green LED lights up, but Even pressing the power button it doesn't turn on.
=== Update (12/12/23) ===
[image|3175412]
I decided to test the power supply with a multimeter, using this Apple manual as a reference.
Pin 3 is not supplying voltage.
Pin 4 is supplying 12v, as Led 1 is on when the AC cable is connected.
Pin 11 starts supplying 12V after pressing the power button. It corresponds to LED 2, but LED 2 does not light up after pressing the power button and the iMac does not turn on.
Pin 12 starts to supply 12V after pressing the power button.
+
+
=== Update (12/13/23) ===
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+
[image|3175853]
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+
Guys, I was using the incorrect technical manual, I found the one for the iMac 21.5 Late 2009 and did the voltage test using the pins on the logic board.
+
+
-Pin 4 has 12v when I connect the AC cable and LED 1 lights up.
+
+
-Pin 11 is at 0v when the iMac is off. When I press the power button it goes to 12v, but LED 2 doesn't light up and the computer doesn't turn on.
+
+
-Pin 12 is at 4.6v, when I press the power button, it drops to 0v.
Guys, my iMac turned off and doesn't want to turn on again, I realized it was very hot, I even thought it could be some overheating protection, but after hours of turning it off it won't turn on, I notice that when the plug is plugged in, a green LED lights up, but Even pressing the power button it doesn't turn on.
+
+
=== Update (12/12/23) ===
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[image|3175412]
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I decided to test the power supply with a multimeter, using this Apple manual as a reference.
+
+
Pin 3 is not supplying voltage.
+
+
Pin 4 is supplying 12v, as Led 1 is on when the AC cable is connected.
+
+
Pin 11 starts supplying 12V after pressing the power button. It corresponds to LED 2, but LED 2 does not light up after pressing the power button and the iMac does not turn on.
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Pin 12 starts to supply 12V after pressing the power button.
Guys, my iMac turned off and doesn't want to turn on again, I realized it was very hot, I even thought it could be some overheating protection, but after hours of turning it off it won't turn on, I notice that when the plug is plugged in, a green LED lights up, but Even pressing the power button it doesn't turn on.