What Can One Do If iMac Fans Run at Full Speed Once Device Turns on?

Have you noticed some unusual noise or your iMac’s fans running at full speed after turning on the computer? Those are the fans that make a weird noise.

imac fan
Source: bgr.com


Switching off the machine and turning it on again is a universal solution to many problems with Apple products, but not this time. Well, it can fix this issue as well, but not always.

Try pushing the iMac power button during the process of connecting the power cord. You will notice that your Apple device will turn into a mode that allows the fans working at full speed. Because of the noise and resources, it is obvious that a Mac owner may want to fix this problem with fans somehow.

The top recommended solution is to reset the System Management Controller on Mac. It is also known as the SMC. It is not that difficult, so you do not need a rich experience to do that. Once you are done, make sure that your device starts to function as expected without making too much noise and getting overheated.

Once again, before you apply the recommended fix, boot your Mac by pushing the power button after connecting the power cord.

Resetting SMC

Two methods exist to rest SMC, and you should choose the one based on whether your computer has a non-removable or removable battery. In the first case, take the offered steps to deal with misbehaving fans on your Mac:

  • Select Apple menu and Shut Down.
  • Push the combination of three keys after the first step: Shift, Control, and Option. Next, push the power button at the same time. Hold all four buttons for about ten seconds.
  • Let the buttons go. Push the power button once more to switch on the target Apple device.

In case of the removable battery inserted in your computer, do the following:

  • Switch off the Mac.
  • Take away the battery. An Apple Authorized Service Provideror Apple Retail Store will help if you get stuck.
  • Push and keep holding the power button. Do it for at least five seconds.
  • Reinsert the battery.
  • Push the power button once more to switch on the Apple computer.

Apply Activity Monitor to Kill Runaway Processes

Activity Monitor, a native Apple’s utility set by default on your iMac and other models of Mac, helps to handle many problems, and the one with fans is among them. You just need to do everything properly.

How can the offered method help? Well, runaway apps often reduce the battery runtime significantly. They also adversely impact overall performance and increase the heat as well as fan activity.

  • Launch Activity Monitor from the Applications folder.
  • Check the malfunctioning processes in the CPU tab of the tool.
  • Decide which processes require most of the CPU. Attempt to shut down the process in a normal way before taking the measures of last resort. For instance, try stopping Safari by moving to the browser and selecting Safari → Quit Safari.

In a situation when you cannot shut down the app normally, apply Activity Monitor. It has an option called Force Quit. It is not recommended, but still a way out. Make sure to store any docs associated with the process. Choose the application in the Activity Monitor list. Select View → Quit Process then.

The best way to prevent malfunctioning apps, make sure your software, plug-ins, and installed OS are up-to-date. Upgrade them regularly.