How To Reset PRAM & SMC On Your Mac.
Mac is a reliable computer, but on rare occasions it can start to behave strangely or crash for no apparent reason.
You may notice some strange behavior, such as the keyboard not responding as expected, the lights and indicators are not working properly, or the operating system is running slower than usual. Other strange symptoms might include your Mac refusing to charge properly, going to sleep unexpectedly, or not booting at all.
Some of these problems can be resolved with a basic reboot and other troubleshooting tips. However, if they persist, you will need to reset PRAM and SMC on your Mac.
What is PRAM and SMC?
PRAM (Parameter RAM) stores important information about your Mac’s control settings. These settings include display, time zone, speaker volume, and more. The PRAM is powered by an internal battery, so your settings are not lost even when you turn off your Mac.
In modern Mac computers, PRAM is known as NVRAM (Non-Volatile RAM), which serves the same purpose as PRAM. The main difference between PRAM and NVRAM is that while both can be damaged, this is not so common with NVRAM.
The SMC (System Management Controller) is built into the Intel-based Mac motherboard and manages the basic tasks of your Mac. Tasks such as power, lighting, fans, and system performance are subject to the SMC.
When your Mac starts to behave strangely, you can reset PRAM and SMC to get your Mac back up and running.
When should I reset PRAM on Mac?
As we have seen, PRAM / NVRAM on your Mac manages basic control parameters such as speaker volume, mouse speed, boot fonts, boot disk, virtual memory, disk cache, port configuration, and many other operational aspects. You can tweak these settings, but you can also reset PRAM / NVRAM to fix several issues, including:
- Wrong date and time or wrong time zone.
- Sound volume does not change.
- Mac keeps booting from the wrong disk.
- A question mark appears at startup.
- Strange mouse scrolling speed
- Screen resolution does not change.
When should you reset SMC on your Mac?
SMC, on the other hand, controls the basic hardware functions of your Mac, so if you run into one or more problems with such basic tasks, you will need to reset the SMC.
These issues include, but are not limited to:
- Mac unexpectedly hibernates or shuts down.
- The keyboard backlight, battery indicator, display backlight, and status lights are not working properly.
- The battery is not charging properly.
- Incorrect display brightness.
- Mac is unusually slow, even with low CPU usage.
- The fans are loud and fast.
- The Bluetooth and USB ports are not working.
- External devices are not recognized.
- The power button is not working well.
- Mac does not respond as expected when you open or close the lid.
- Doesn’t wake up or go to sleep.
- The power indicator is not displayed or is displayed incorrectly.
- The target display mode is working correctly.
- Bouncing dock icons keep bouncing without opening associated apps.
How to reset PRAM on your Mac
Resetting your Mac should be your last resort when troubleshooting methods such as reboots and other tricks to speed up your slow computer fail.
Before you can reset PRAM and SMC on your Mac, make a final backup of all your critical data. You can save them to an external drive or USB drive. In addition, you need to turn off all speakers, dongles, drives, external displays and keyboards so that nothing gets in the way of the factory reset process.
Resetting PRAM / NVRAM on your Mac sets the hard drive as boot drive and restores hardware defaults.
- To reset PRAM / NVRAM, shut down your Mac, turn it on, and press and hold the Option, Command, P, and R keys together. Release the keys after about 20 seconds and your Mac will reboot.
Note. If your Mac plays a startup sound, release the four keys after the second startup sound. If you have a Mac with an Apple T2 Security Chip, release the keys after the Apple logo appears and then disappears a second time.
- If your Mac uses a firmware password (which means other users without a password can only start from the specified boot drive), you will have to disable the firmware password before resetting NVRAM.
- When startup is complete, open System Preferences and adjust any settings that have been reset, such as screen resolution, sound volume, time zone, or boot drive selection. To open System Preferences, click Apple menu System Preferences, or click the System Preferences icon in the Dock.
Note. On Mac desktop computers, you may need to replace the battery if settings such as time zone or sound volume are reset every time you turn off and turn off your computer.
How to reset SMC on your Mac
Resetting the SMC on your Mac restores the default settings associated with low-level settings that you cannot change in system preferences. Resetting the SMC depends on the Mac you are using, whether it has a removable or built-in battery, and whether it’s plugged in.
- To reset SMC on your Mac, you will need to shut down your Mac. If your computer won’t turn off, press and hold the power button for about 10 seconds or until your Mac turns off.
- If your Mac has the Apple T2 Security Chip, shut down your computer, press and hold the power button, and then release it after 10 seconds.
- Press the power button to turn on your Mac.
- If your Mac is still not responding as expected, shut it down, and then simultaneously press and hold the Control, Option, and Shift keys for about 7 seconds. Also press and hold the power button and wait for the Mac to shut down.
- Hold down the Control, Option, Shift, and Power keys for another 7 seconds and then release them.
- Press the power button to turn on your Mac and check again to see if it is working normally.
For Mac desktops with the Apple T2 Security Chip, shut down the computer and unplug the power cord. Wait 10-15 seconds, reconnect the power cord, and then press the power button after 5 seconds to turn on the computer.
Note. Resetting the SMC does not affect the contents of the PRAM / NVRAM.
- To reset the SMC on Mac computers without the Apple T2 Security Chip, shut down the Mac. , press and hold the Shift, Control, and Option keys.
- While holding down the Shift, Control, and Option keys, press and hold the Power button. Hold all four keys for 10 seconds.
- Release the four keys after 10 seconds and press the power button to turn on your Mac.
If you have a Mac laptop with a removable battery, shut down your Mac and remove the battery. Press and hold the power button for 5 seconds, reinstall the battery, and then press the power button to turn on your Mac.
On Mac desktops without the Apple T2 Security Chip, shut down the Mac, unplug the power cord, and wait 15 seconds before plugging the cable back in. Wait another 5 seconds and then press the power button to turn on the computer.
If resetting PRAM / NVRAM or SMC doesn’t work, try using Apple Diagnostics or Apple Hardware Test (for Macs manufactured before June 2013). These tests contain a set of diagnostic tools that check your Mac for hardware problems, suggest solutions, and help you contact Apple Support for further assistance.
Make your Mac up again
If your Mac is misbehaving, resetting PRAM or SMC (or both) will get it back to working as you expect. Is your Mac working properly after following these steps? Share with us in the comments.