If the USB ports of your MacBook Pro keep malfunctioning, and you’ve already checked and confirmed that the USB device(s) you’re trying to connect are not the culprit, you may need to do something about the USB ports.
There are two ways you can fix all the problematic USB ports in a single go:
[listNum]■Reset System Management Controller (SMC)
SMC is a chip inside your MacBook Pro that manages the components that require power to function. Resetting SMC puts the configuration of all such components to their factory defaults, thus making the non-functioning/unresponsive USB ports work properly.
■Reset Non-Volatile Random Access Memory (NVRAM) or Parameter Random Access Memory (PRAM)
NVRAM (or PRAM in old MacBook) stores the system settings such as date, time, screen resolution, etc. Resetting NVRAM restores these settings back to default. This resolves many MacBook issues (including malfunctioning USB ports) within a few minutes.
Resetting SMC and NVRAM (PRAM) is simple.
Resetting SMC requires your MacBook Pro to completely cut off from any power supply. The older MacBook Pro computers had removable battery and therefore the process of resetting SMC in them was slightly different than it is in newer MacBook Pro.
To help all Mac users, resetting SMC on both types of MacBook Pro is explained below:
Reset SMC on MacBook Pro without Removable Battery
- ■Shut down your MacBook Pro
Click the Apple logo from the top-left corner, click Shut Down from the menu, and click Shut Down again in the box that appears next. This shuts down your MacBook Pro. This step is not required if your MacBook Pro is already turned off.
■Remove the power and devices
Disconnect your MacBook Pro from the power supply, and remove all the connected devices from the USB ports. This isolates your MacBook Pro. Dong so ensures that your computer has no power supply, and no harm can be caused to the USB devices or your important data.
Press and hold down the Control + SHIFT + Option (Alt) + Power (Eject) keys together on your computer’s built-in keyboard for 10 seconds, and then release the keys. This resets the System Management Controller (SMC) on your MacBook Pro. Any issues with the components that require some power to operate are resolved in this step.
■Boot MacBook Pro
Connect your MacBook Pro back to the power supply after resetting SMC, and press the Power (Eject). This boots your computer normally. Upon booting, you are displayed with the login screen.
■Check if the solution worked
Log in to your Mac, connect a USB device to one of its culprit ports. If you followed the process correctly, the USB device should be able to connect and function properly this time.
Reset SMC on MacBook Pro with Removable Battery
- ■Shut down your MacBook Pro, disconnect it from the power supply, and remove all the devices connected to its USB ports as explained in the 1st and 2nd steps of the previous section.
■Remove the battery from your MacBook Pro as well.
■Press and hold down the Power button for 5 seconds, and release the button after that.
■After resetting SMC, put the battery back in its socket, plug your MacBook Pro to the power supply, and press the Power button to boot your computer.
■Confirm if the USB ports can function normally.
Reset NVRAM (PRAM)
Unlike resetting SMC, the process to reset NVRAM (PRAM) is identical for both MacBook Pro with removable battery and without one.
Here’s how you reset NVRAM (PRAM) on your MacBook Pro:
Note: You can skip resetting NVRAM (PRAM) if the USB ports started functioning after you reset SMC on your MacBook Pro.
- ■Initiate restart
Click the Apple logo, click Restart, and click Restart in the box that appears next. This shuts down your MacBook Pro only to automatically power up again. NVRAM can be reset during this transition phase. If your MacBook Pro isn’t on, you can press the Power (Eject) button, and immediately follow the instructions in the second step.
Immediately press and hold down the Command + Option (Alt) + R + P keys together when your MacBook Pro powers up again after shutting down, and release the keys only after the gray screen goes black momentarily and then gets gray again. This resets the NVRAM (PRAM) of your MacBook Pro, thus resolving any configuration and setting issues (including those with the USB ports) the computer may have. Upon booting, you may need to reconfigure the system settings.
■Check and confirm if the USB ports are able to function normally.