iMac (27-inch, Late 2009): Fans run at full speed after installing SMC update

Products Affected

iMac (27-inch, Late 2009)

Symptoms

In some situations, after you apply the iMac SMC Firmware Update 1.0 the iMac fans run at full speed.

Resolution

The SMC update has not applied properly.  To verify that the SMC update has not applied:

  1. Choose About this Mac from the Apple () menu. 
  2. Click More Info. 
  3. Examine the "SMC Version (system)" field in the Hardware Overview pane.  If this field displays 0.00, the SMC Update did not apply properly.
  4. To address this issue, download and install the iMac SMC Firmware Update 1.0 again.
  5. If this does not correct the condition, contact AppleCare, an Authorized Apple Service Provider, or bring your computer to an Apple Store.   If you plan to visit an Apple Retail store, make a reservation at the Genius Bar using http://www.apple.com/retail/geniusbar/ (available in some countries only).
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