Specifications
Rear housing includes the following parts:
Wi-Fi antenna in silver circle behind Apple logo
Microphone
Power button and cable
AC inlet
Gaskets
Wireless antenna insulators
Important: Replacement of any of these parts require replacement of the entire rear housing. These components are not available
as individual parts.
Always handle rear housing with two hands in the lower left and right corners.
Never carry the rear housing with a single hand or push in or pull out on the chin.
Handling rear housing part incorrectly could flex aluminum and cause alignment issues.
Service Procedures
Resetting the System Management Controller (SMC)
The System Management Controller (SMC) is a chip on the logic board that controls all power functions. If the computer is experiencing any power
issue, such as not starting up, not displaying video, sleep issues, or fan noise issues, resetting SMC may resolve it.
Refer to Apple Support article HT3964 for SMC reset instructions.
Resetting the SMC means you will also need to reset the date and time (using the Date & Time pane of System Preferences).
If you press the power button while inserting the power cord, the iMac will enter a mode in which the fans run at full speed.
Refer to Apple Support article TS1433.
Coin Battery Testing, RTC Reset, and Coin Battery Removal
The iMac utilizes a coin battery located on the logic board to provide power to the real time clock (RTC) and parameter RAM (PRAM) when the iMac is