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I have a late 2009 21.5" iMac and the fan runs at full speed constantly. My friend knows a lot more about iMacs than I do and so she tried some resets and has also run some tests on it. She found that the optical drive temperature sensor needs to be replaced. I have ordered the part (922-9214) and would like a step by step guide on how to put it in the machine. I have a cousin and a friend who have both pulled apart and put together computers before, so I am planning to ask one of them to put it in for me, but I want to give them a guide to follow. Any help would be much appreciated. Thanks.
The guide you want your cousin to follow is this one: iMac Intel 21.5" EMC 2308 Optical Drive Replacement Step17 gets into the taking it off. the drive. Frankly, You really don’t need to pull the drive out only loosen it a bit to sneak the cable out as the sensor is right on top, just get to Step10 (you can even see it in the guide picture below). I would recommend you run this great app first to be doubly sure: TG Pro It will show you the sensors and fans. If you buy the full version it can give you a diagnostic on your systems cooling.
