How to reset the SMC on your Mac

What the SMC does

The System Management Controller looks after the low-level hardware on Intel Macs: power, charging, fans, sleep and wake, the keyboard backlight and status lights. When it gets confused, the Mac can behave strangely even though nothing is actually broken.

Signs an SMC reset might help

Fans running flat out when the Mac isn’t busy. A MacBook that won’t charge or shows the wrong battery level. Not waking from sleep, shutting down unexpectedly, or ports and the keyboard backlight not working properly.

First, check which Mac you have

Click the Apple menu and choose About This Mac. If it lists a Chip such as Apple M1, M2, M3 or M4, you have Apple silicon. If it lists a Processor such as Intel Core i5, you have an Intel Mac.

Apple silicon Macs (M1 and later)

There’s no separate SMC to reset. The same job is handled automatically when the Mac restarts.

1. Choose Apple menu, then Shut Down.

2. Wait at least 30 seconds.

3. Press the power button to turn it back on.

Intel MacBooks with the T2 chip (most 2018 to 2020 models)

1. Shut down the Mac.

2. Press and hold Control and Option on the left side and Shift on the right side for 7 seconds.

3. Keep holding those keys and also press and hold the power button for another 7 seconds.

4. Release all the keys, wait a few seconds, then turn the Mac on.

Intel MacBooks without the T2 chip (2009 to 2017)

1. Shut down the Mac.

2. Press and hold Shift, Control and Option on the left side of the keyboard and the power button, all together, for 10 seconds.

3. Release all the keys and turn the Mac on.

Intel desktops (iMac, Mac mini, Mac Pro)

1. Shut down the Mac and unplug the power cable.

2. Wait 15 seconds.

3. Plug the cable back in and wait another 5 seconds.

4. Turn the Mac on.

Still not right?

If the fans are still racing or it still won’t charge, the fault is probably hardware: a failed sensor, charging circuit or something on the logic board. That’s exactly the kind of board-level repair we specialise in. Diagnosis is free and there’s no fix, no fee.