The SMC, or System Management Controller, is a subsystem of Mac computers containing Intel chips that controls certain hardware functionality. You can reset the SMC of your MacBook Pro if you experience certain hardware issues by disconnecting the battery and power cable then pressing the Power button to drain the capacitors of any remaining power. Unfortunately there is no confirmation message that appears when you reset the SMC; the only way to confirm that you've successfully reset the MacBook Pro SMC is to verify that all of the systems the SMC controls are working properly.
Power on your MacBook Pro and listen to the internal fans. If the fans run at full speed and are noisy constantly, even when the system is not running any processes or is already cool, the SMC reset was unsuccessful.
Click on "Apple" in the file menu on the Mac desktop and select "Sleep." Press the "Power" button to wake your MacBook Pro. If the MacBook Pro will not enter sleep mode or will not wake from sleep mode or if the "Power" button is unresponsive or the system randomly shuts down, the SMC reset was unsuccessful.
Hold your hand over the ambient light sensor next to the Web cam on the MacBook Pro screen. Verify that the screen brightness automatically adjusts to the change in light. If the screen does not adjust or if the keyboard backlights do not work, the SMC reset was unsuccessful. Note that some models of MacBook Pro do not offer this feature; ensure that your model offers ambient light adjustment before testing.
Run applications on the MacBook Pro and look for abnormal system slowdown, especially apparent when running very few applications. If the computer displays any of these symptoms, the SMC reset was unsuccessful.
Plug peripherals into the ports on the computer and attempt to connect to a Wi-Fi network using the AirPort feature. If the MacBook does not recognize the devices or will not connect to the network, the SMC reset was unsuccessful.