How to Fix ‘Sleep/Wake Hang Detected’ Error on MacBook

I keep receiving the error - panic(cpu 1 caller 0xfffffff0256548a4): “Sleep/Wake hang detected” when my MacBook goes to sleep. The key point is that my MacBook is disconnected from a power source when it enters sleep mode. Does anyone know what the “Sleep/Wake hang detected” error means? I’m tired of this error, can anyone tell me how to fix the “Sleep/Wake hang detected” error on Mac?

When the error panic(cpu 1 caller 0xfffffff0256548a4): “Sleep/Wake hang detected” occurs on your MacBook, it means your Mac is experiencing a kernel panic related to sleep and wake functionality.

In more detail, the operating system encounters a serious issue when it attempts to either go into sleep mode or wake up from it. During this transition, the system hangs or freezes, making the macOS kernel trigger a panic for diagnostic purposes.

The reasons why you keep receiving the “Sleep/Wake hang detected” error when your Mac goes to sleep or wakes up from it are below:

Your Mac has hardware problems. Your Mac’s battery, logic board, keyboard, or other components have certain malfunctions.

macOS bugs.

Third-party kernel extensions that interfere with the proper sleep/wake behavior.

Connected external devices may interfere with the MacBook’s ability to transition between sleep and wake states.

Certain critical system data related to power management is corrupted.

Incorrect wake and sleep-related settings.

Different reasons can lead to the “Sleep/Wake hang detected” error on your MacBook, including system bugs, hardware issues, peripheral interference, faulty sleep and wake-up settings, etc. Therefore, you need to try a series of ways to troubleshoot this issue.

Here are the ways we concluded to fix the “Sleep/Wake hang detected” error on the Mac.

Disconnect all external devices

Whether you use a wired mouse, keyboard, USB hub, or external hard drive, disconnect it from your Mac. Then, let your Mac go to sleep mode and wake up from it, and then observe if the error shows up again or not.

If not, reconnect all your external devices to your Mac one by one, and meanwhile enter sleep mode and wake up your Mac from it until you find the culprit that resulted in this error.

Check the sleep and wake-up-related settings of your Mac

  1. Click the Apple menu > System Settings.

  2. Select Battery > Options.

  3. Change the option for Enable Power Nap to Never.

  4. Click Done.

Reset SMC

SMC (System Management Controller) is a chip on Intel-based Macs that manages power, battery, keyboard, display, and related functions. When your Mac sleep or wake-up performs improperly, you can reset SMC to fix it.

  1. Completely turn off your Mac.

  2. Reboot your Mac and meanwhile press and hold the Shift - Control - Option keys on the left side of the keyboard for about 10 seconds.

  3. Release the keys.

Then, check if the “Sleep/Wake hang detected” error occurs or not when your Mac goes to sleep or wakes up from it.

Boot your Mac to Safe Mode

Safe Mode is regarded as a special mode that only uses the minimum of drivers for booting up the Mac while isolating all third-party software. Meanwhile, when safe boot your Mac, the startup disk will be verified and the found directory issues will also be fixed.

So, when your Mac has issues when going to sleep mode or waking up from it, you can boot your Mac to Safe Mode to check the startup disk and verify if the third-party software causes this error.

If your Mac can enter sleep or wake up from it normally in Safe Mode, go to uninstall the recently installed third-party software.

Update your Mac

Have you recently updated to the new macOS like macOS 15.0 Sequoia? Usually, the initial version of a new macOS version has some bugs. If there’s a minor update available, go to update your Mac.