Before Resetting the SMC

1. Press Command + Option + Escape to force quit any application that is not responding.
2. Put your Mac to sleep by choosing the Apple () menu from the upper-left menu bar and then choosing Sleep. Wake the computer after it has gone to sleep.
3. Restart your Mac by choosing the Apple menu from the upper-left menu bar and then choosing Restart.
4. Shut down your Mac by choosing the Apple menu from the upper-left menu bar and then choosing Shut Down.

1. Unplug the MagSafe power adapter from the Mac and the wall power socket for several seconds.
2. Shutdown the Mac. Physically remove and re-insert the battery (if it's removable) and startup the Mac.

Indicators

Fans

• The computer's fans run at high speed although the computer is not experiencing heavy usage and is properly ventilated.

Lights

• The keyboard backlight appears to behave incorrectly (on Mac computers that have this feature).
• The Status Indicator Light (SIL) appears to behave incorrectly (on Mac computers that have an SIL).
• Battery indicator lights, if present, appear to behave incorrectly (on portables that use non-removable batteries).
• The display backlight doesn't respond correctly to ambient light changes on Mac computers that have this feature.

Power

• The computer doesn't respond to the power button when pressed.
• A portable Mac doesn't appear to respond properly when you close or open the lid.
• The computer sleeps or shuts down unexpectedly.
• The battery does not appear to be charging properly.
• The MagSafe power adaptor LED doesn't appear to indicate the correct activity.

System performance

• The computer is running unusually slowly although it is not experiencing abnormally high CPU utilization.
• Application icons may "bounce" in the Dock for an extended amount of time when launched.
• Applications may not function correctly or may stop responding after being opened.

Video

• A computer that supports target display mode does not switch into or out of target display mode as expected.
• A computer that supports target display mode switches into or out of target display mode at unexpected times.

Port illumination

• The illumination around the I/O ports on a Mac Pro (Late 2013) does not activate when you move the computer.

Resetting the System Management Controller (SMC)

Resetting the SMC on Mac portables with a battery you can remove

1. Shut down the computer.
2. Disconnect the MagSafe power adapter from the computer, if it's connected.
3. Remove the battery.
4. Press and hold the power button for 5 seconds.
5. Release the power button.
6. Reconnect the battery and MagSafe power adapter.
7. Press the power button to turn on the computer.

Resetting the SMC on portables with a battery you should not remove on your own

1. Shut down the computer.
2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
4. Release all the keys and the power button at the same time.
5. Press the power button to turn on the computer.
   Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.

Resetting the SMC for Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve

1. Shut down the computer.
2. Unplug the computer's power cord.
3. Wait fifteen seconds.
4. Attach the computer's power cord.
5. Wait five seconds, then press the power button to turn on the computer.

Learn more

• Responding to presses of the power button
• Responding to the display lid opening and closing on portable Macs
• Battery management
• Thermal management
• The SMS (Sudden Motion Sensor)
• Ambient light sensing
• Keyboard backlighting
• Status Indicator Light (SIL) management
• Battery status indicator lights
• Selecting an external (instead of internal) video source for some iMac displays