How to reset SMC on MacBook？

Have you recently replaced your MacBook battery or logic board? Or are you dealing with strange issues like your MacBook not charging, fans running loudly, or the power button not responding? One of the most effective first steps is to reset your MacBook’s SMC (System Management Controller).

In this guide, we'll explain what the SMC does, when to reset it, and how to perform an SMC reset on different MacBook models, including MacBook Pro, MacBook Air, and older MacBooks with removable batteries.

What Is the SMC on a MacBook?

The System Management Controller (SMC) is a low-level chip that controls several important hardware functions on Intel-based MacBooks, such as:

• Power management (startup, shutdown, sleep)

• Battery charging and performance

• Fan speed and thermal management

• LED indicators (battery status light, keyboard backlight)

• Display backlighting and ambient light sensor

Resetting the SMC can help fix many MacBook hardware-related problems, especially those that persist after hardware replacements.

When Should You Reset the SMC?

You should consider an SMC reset if your MacBook is experiencing:

• Battery not charging or charging slowly

• Power button not working

• Fans running at full speed for no reason

• Mac not turning on or waking from sleep properly

• Unexpected shutdowns or sleep issues

• Incorrect status lights or LED indicators

• You recently replaced the battery or motherboard

These symptoms are often signs of a misbehaving system controller, and an SMC reset is a safe and easy troubleshooting step.

Does Your MacBook Have a Non-Removable Battery?

Before you reset the SMC, it’s important to know whether your MacBook has a removable or non-removable battery, as the steps vary slightly.

• Non-removable batteries: Found in most MacBooks made after mid-2009, including all MacBook Pro and MacBook Air models.

• Removable batteries: Found in older MacBooks (mostly pre-2009), with a visible latch on the bottom to release the battery.

Let’s break down the reset steps based on your model type.

How to Reset SMC on a MacBook

For MacBooks with Non-Removable Batteries

MacBook with T2 Security Chip (2018 and later)

This includes most modern MacBook Air and MacBook Pro models.

1. Shut down your Mac completely.

2. Press and hold the right Shift, left Option, and left Control keys for 7 seconds.

3. While holding those keys, press and hold the Power (Touch ID) button for another 7 seconds.

4. Release all keys and wait a few seconds.

5. Press the power button to turn on your Mac.

MacBook without T2 Chip (2017 and earlier)

1. Shut down your Mac.

2. Press and hold Shift (left) + Control (left) + Option (left) + Power button for 10 seconds.

3. Release all keys.

4. Press the power button to boot your MacBook.

For Older MacBooks with Removable Batteries

If you're using a pre-2009 MacBook or MacBook Pro with a removable battery:

1. Shut down your Mac and unplug the power adapter.

2. Remove the battery.

3. Press and hold the power button for 5 seconds.

4. Reinstall the battery and reconnect the power adapter.

5. Turn on your Mac.

Will Resetting the SMC Delete My Files?

No. Resetting the SMC only affects low-level hardware settings. Your personal data, apps, and system preferences will remain untouched. It’s a completely safe process and often the quickest way to restore normal functionality.

Bonus Tip: What About PRAM or NVRAM?

If you're still having issues after the SMC reset, try resetting your NVRAM/PRAM:

1. Shut down your Mac.

2. Turn it on and immediately press and hold Option + Command + P + R.

3. Keep holding for about 20 seconds, then release the keys.

PRAM and NVRAM store settings like display resolution, startup disk preferences, and sound volume—useful to reset alongside SMC in some cases.

This simple reset can resolve many frustrating issues in minutes. If the problem persists, however, it may point to a deeper hardware issue, and it’s best to consult Apple Support or a certified technician.