Mac Won’t Wake From Sleep: Display and Power Fixes

2 Sep 2026

You open your MacBook, press a key or click the mouse—and nothing happens.

The screen remains black, an external monitor reports no signal, or the Mac appears to be awake because you can hear notifications and fans, but no picture appears. In other cases, the display eventually returns only after disconnecting a dock, forcing a restart or opening and closing the lid several times.

A Mac that will not wake properly can have several different causes:

The Mac has run out of power
The display has failed to wake even though the Mac is running
An external monitor, cable or dock has lost its connection
A background application or accessory has disrupted sleep
macOS or a device driver has become stuck
An Intel Mac has a power-management problem
A hardware fault is affecting the battery, display or logic board

The safest way to diagnose it is to establish whether the Mac itself is asleep, whether only the display is black, or whether the computer has actually powered off.

First, Try the Normal Wake Methods

A Mac should normally wake when you:

Open the lid of a MacBook
Press a key
Click the mouse or trackpad
Press the Touch ID or power button briefly

Apple lists opening the display, pressing a keyboard key and clicking a mouse or trackpad as the normal methods for waking a Mac.

Wait several seconds after each attempt. A Mac connected to multiple displays, docks or external drives may take slightly longer to restore the desktop.

Avoid repeatedly pressing the power button, because a long press can force the Mac to shut down.

Check Whether the Mac Is Actually Awake

Before assuming the whole computer is frozen, look for signs of activity:

The Caps Lock light responds
The keyboard backlight turns on
You hear notification sounds
The Touch Bar or Touch ID responds
Fans are running
An external drive is active
The mouse pointer appears briefly
The Mac responds to volume keys
Another computer can still access a shared folder on it

If these signs are present, the Mac may be awake while the display remains black.

That points more strongly towards a display, cable, graphics or external-monitor problem than a total power failure.

Increase the Screen Brightness

The display may have woken at its lowest brightness level.

Press the brightness-up key several times. On some keyboards, you may need to hold the Fn key while pressing the brightness control.

For an external monitor, use the controls built into the display and confirm that:

It is powered on
The correct input is selected
Brightness is not set to zero
The monitor is not in its own deep-sleep mode

A dark display can sometimes look identical to a Mac that has failed to wake.

Connect the Power Adapter

A MacBook may have discharged while sleeping, particularly if:

It was left asleep for several days
A connected device continued drawing power
An application prevented proper sleep
The battery is ageing
The lid was closed while a demanding task was running

Connect a known-good power adapter directly to the Mac and leave it charging for at least several minutes.

Apple recommends connecting power, disconnecting other accessories and allowing a MacBook battery to reach at least 10% charge before reconnecting external devices when the screen is black because the battery may be depleted.

Check whether the charging sound, battery icon or MagSafe indicator appears.

Where possible, avoid testing through a dock. Connect the charger directly to the Mac.

Disconnect All Accessories

USB and Thunderbolt accessories can interfere with sleep, wake and display detection.

Disconnect everything except power, including:

USB hubs
Thunderbolt docks
External displays
Storage drives
Printers
Audio interfaces
Capture devices
Ethernet adapters
SD cards
Phones and tablets

Then try waking the Mac again.

Apple advises disconnecting accessories when a Mac does not appear to power on, because a connected device, hub or cable may be involved.

If the Mac wakes correctly without accessories, reconnect them one at a time. Put the Mac to sleep and wake it after reconnecting each item.

This can identify a faulty dock, cable or peripheral.

Force the Display to Refresh

When the Mac appears to be awake but the screen remains black, try actions that may force macOS to redraw the display:

Press the brightness-up key.
Move the pointer or click the trackpad.
Press Command + Tab to switch applications.
Press Control + Command + Q to call the Lock Screen.
Close the MacBook lid, wait several seconds and reopen it.
Disconnect and reconnect the external display.

Do not close the lid if the Mac is extremely hot or appears to be performing an important update.

Check the External Display’s Input

Many monitors support several inputs, such as:

HDMI 1
HDMI 2
DisplayPort
USB-C
Thunderbolt

The monitor may have switched inputs during sleep.

Use its physical controls to select the port connected to the Mac.

Also check whether another connected device—such as a games console or second computer—has taken control of the input.

Reconnect the Display Cable

Disconnect the video cable at both ends, wait a few seconds and reconnect it securely.

Check for:

Loose USB-C connectors
Damaged HDMI plugs
Bent contacts
A cable under tension
An adapter becoming unusually hot
A dock that has lost power

Apple recommends checking display power, cables, ports and adapters when an external display is not recognised.

Try a different port on the Mac where one is available.

For example, move the cable from one Thunderbolt port to another.

Test Without the Dock

Docks are frequent contributors to wake problems because one device may be handling:

Display output
Charging
USB devices
Ethernet
Audio
External storage

Disconnect the dock and connect the monitor directly to the Mac using a suitable cable or adapter.

If the display wakes reliably when connected directly, the likely causes include:

Dock firmware
Dock power supply
Cable bandwidth
DisplayLink software
Port limitations
A faulty dock

Check the dock manufacturer’s support information for firmware or driver updates.

Use Detect Displays

If the Mac wakes but does not recognise the external monitor:

Open System Settings.
Select Displays.
Hold the Option key.
Select Detect Displays when it appears.

Apple documents holding Option in Displays settings to reveal the Detect Displays control when a connected display has not been recognised.

If the display still does not appear, reconnect it directly and restart the Mac.

Check the Cable’s Capabilities

A cable can fit physically but still fail to support the required:

Resolution
Refresh rate
HDR mode
Display bandwidth
Charging power

A lower-quality USB-C cable designed primarily for charging may not reliably carry video.

Apple notes that an external display may remain dark or use a reduced resolution or refresh rate when the cable or adapter does not support the requested display configuration.

Test with:

The cable supplied with the monitor
A certified Thunderbolt cable
A known-good HDMI cable
A direct connection without adapters

Avoid connecting several adapters together.

Reduce the Resolution or Refresh Rate

A display may wake unreliably when running at a resolution or refresh rate that pushes the limits of the cable, adapter or dock.

Open:

System Settings > Displays

Temporarily select:

The default resolution
A lower refresh rate
Standard dynamic range instead of HDR
A simpler display arrangement

Apple’s Displays settings allow the resolution, refresh rate and other supported display options to be adjusted, although available controls vary by Mac and monitor.

Test several sleep-and-wake cycles after changing the setting.

Check Whether the Mac Supports the Display Setup

Mac models differ in how many external displays they can operate and at which resolutions.

Problems may occur after wake when the setup includes:

Several high-resolution displays
Daisy-chained monitors
A high-refresh gaming display
DisplayLink adapters
Multiple docks
A television and monitor combination

Apple advises checking the technical specifications for the exact Mac model to confirm the supported number, resolution and refresh rate of connected displays.

A configuration that works intermittently may still exceed what the Mac, dock or cable can support reliably.

Restart the Mac

A normal restart clears stuck display, graphics and power-management processes.

Where the Mac is responding, choose:

Apple menu > Restart

After restarting:

Sign in.
Leave accessories disconnected.
Test sleep and wake.
Reconnect devices gradually.

For Apple silicon Macs, restarting is also Apple’s recommended equivalent when older guidance might have suggested resetting the System Management Controller.

Force the Mac to Power Off Only When Necessary

If the Mac is completely unresponsive:

Press and hold the power button or Touch ID button for about 10 seconds.
Release it.
Wait several seconds.
Press the power button normally.

Apple recommends a roughly 10-second hold when a Mac will not respond to the power button in the normal way.

This forces the Mac off and can result in unsaved work being lost.

Do not use forced shutdowns routinely. Repeated need for them indicates a problem that should be investigated.

Install macOS Updates

Sleep and wake problems may be corrected by macOS updates.

Open:

System Settings > General > Software Update

Install supported updates after backing up important data.

Also update:

Dock firmware
DisplayLink Manager
Monitor firmware
USB or Thunderbolt device software
Virtualisation applications
Security software

A sleep problem that began immediately after adding software or an accessory should be tested without that item.

Check Login Items and Background Software

Applications that interact with displays, power or connected hardware may contribute to wake failures.

Examples include:

Display-management utilities
Screen-recording tools
Remote-access applications
Dock software
DisplayLink Manager
Colour-calibration tools
Window-management software
VPN clients
Security agents
Virtual machines

Open:

System Settings > General > Login Items & Extensions

Review Open at Login and Allow in the Background.

Temporarily disable non-essential items, restart and test sleep again.

Do not disable business security, backup or device-management software without approval.

Test in Safe Mode

Safe Mode limits third-party software and performs several startup checks.

If the Mac wakes correctly in Safe Mode, the likely cause is:

A login item
A background extension
Third-party software
A cache
An additional driver

Apple silicon Mac

Shut down the Mac.
Hold the power button until startup options appear.
Select the startup disk.
Hold Shift.
Select Continue in Safe Mode.

Intel Mac

Restart the Mac.
Immediately hold Shift.
Release it when the login window appears.

Test sleep and wake more than once.

Restart normally afterwards.

Reset the SMC on an Intel Mac

The System Management Controller manages functions including power, battery charging, thermal behaviour and sleep on Intel-based Macs.

An SMC reset may help when an Intel Mac:

Will not wake
Behaves unpredictably around power
Has charging problems
Runs fans incorrectly
Responds strangely to lid closure

The reset method differs according to whether the Mac has:

An Apple T2 Security Chip
A removable battery
A non-removable battery
A desktop design

Use the instructions for the exact model.

Do not attempt an SMC reset on Apple silicon Macs. Apple states that Apple silicon systems do not need one; restarting the computer is the appropriate step.

What About NVRAM or PRAM?

Intel Macs store some display-related settings in NVRAM, including certain startup and resolution information.

Resetting NVRAM may be worth considering when an Intel Mac repeatedly uses:

The wrong display
An incorrect resolution
Unexpected startup behaviour
A black screen after changing monitors

To reset it on a compatible Intel Mac:

Shut down the Mac.
Turn it on.
Immediately hold:

Option + Command + P + R

Keep holding the keys for approximately 20 seconds.

Apple silicon Macs manage this differently and do not normally require the traditional key-combination reset.

Review Sleep Settings

Open:

System Settings > Lock Screen

Check the options for turning off the display while:

On battery
Connected to the power adapter

Also review Battery or Energy settings, depending on the Mac model.

Options may include:

Prevent automatic sleeping when the display is off
Wake for network access
Low Power Mode
Power Nap-related behaviour

Apple notes that available sleep and energy options vary by model.

A Mac should normally be allowed to sleep. Setting everything to Never may hide the wake problem without fixing it and can increase power use.

Test “Wake for Network Access”

The Wake for network access option allows a sleeping Mac to wake to provide shared resources.

Disable it temporarily if the Mac:

Wakes unexpectedly
Enters an unstable half-awake state
Uses network storage
Provides file or media sharing

Apple explains that this setting can wake a Mac from sleep when another device accesses shared resources.

Test whether disabling it improves reliable sleep and wake.

Check for Applications Preventing Proper Sleep

A Mac that does not enter sleep correctly may fail to wake correctly afterwards.

Open Activity Monitor and select the Energy tab.

Look at the Preventing Sleep column.

Applications that may interfere include:

Media players
Backup tools
Cloud-sync applications
Video calls
Remote desktop software
Virtual machines
File-sharing software
Large exports or renders

Apple notes that applications accessing disks and Spotlight indexing can prevent normal sleep behaviour.

Quit unnecessary applications and test again.

Disconnect External Storage

A malfunctioning or slow external drive can disrupt sleep and wake.

Disconnect:

USB hard drives
SSDs
RAID systems
Memory-card readers
Network-storage adapters

Apple recommends disconnecting USB and Thunderbolt storage devices when investigating sleep problems, then reconnecting them individually to identify a faulty device.

Always eject storage safely before disconnecting it when the Mac is awake and responsive.

Check for Spotlight Indexing

After a macOS update, migration or large file change, Spotlight may index the drive for several hours.

Related processes include:

mds

mdworker

mds_stores

Apple notes that a Mac may not sleep normally while Spotlight indexing is active.

Allow indexing to finish while the Mac is connected to power.

Repeated restarting may delay completion.

Test the Mac Without Bluetooth Devices

A Bluetooth keyboard, mouse or trackpad may fail to wake the Mac even though the Mac itself is healthy.

Try:

The built-in keyboard or trackpad
A wired USB keyboard or mouse
Briefly pressing the power button
Turning the Bluetooth device off and on
Recharging or replacing its batteries

Also check whether a Bluetooth device is unexpectedly waking the Mac through accidental movement or key presses.

Apple notes that keyboard input and mouse or trackpad clicks can wake a Mac, including when those inputs happen unintentionally.

MacBook Works Alone but Not With the Lid Closed

Using a MacBook with the lid closed and an external display is often called closed-display or clamshell mode.

Wake problems in this mode may involve:

The external keyboard or mouse
Power delivery
The display connection
The dock
Bluetooth
Monitor input selection

Test with:

The MacBook connected to power.
The display connected directly.
A wired keyboard or mouse.
The lid initially open.
The external display confirmed working.

Once the desktop appears externally, close the lid and retest.

If the failure occurs only through a dock, investigate the dock rather than macOS first.

Allow a New Display Accessory to Connect

On Apple silicon laptops, macOS may ask for permission before a newly connected USB, Thunderbolt or display accessory can communicate with the Mac.

A display connected while the Mac is locked or asleep may not work until access is approved.

Apple notes that Apple silicon Mac laptops may prompt the user to allow an external display accessory to connect.

Connect the display while the Mac is awake and unlocked, then approve any accessory prompt.

Update the Monitor’s Firmware

Modern monitors and docks contain firmware and can have sleep-related bugs of their own.

Check the manufacturer’s support tools for updates.

This is particularly relevant for:

USB-C monitors
Thunderbolt monitors
Displays with integrated docks
High-refresh monitors
DisplayLink systems
KVM-equipped monitors

Apple recommends checking third-party display documentation and installing current manufacturer firmware where applicable.

Check Whether FileVault Is Involved

After a full shutdown or certain updates, the Mac may be waiting at the FileVault unlock screen rather than waking into the desktop.

The display may appear black if:

The external monitor is not active at the login stage
The MacBook lid is closed
The login screen appears only on the built-in display
The keyboard is not connected

Open the lid, use the built-in display and enter the account password.

Touch ID may not be available immediately after a restart, requiring the password instead.

Run Apple Diagnostics

Use Apple Diagnostics if sleep and wake problems continue after software and accessory testing.

It can check certain hardware components and may identify problems involving:

Logic board
Memory
Power system
Sensors
Battery
Other hardware

Apple silicon

Shut down the Mac.
Hold the power button until startup options appear.
Press and hold Command + D.

Intel

Turn on the Mac.
Immediately hold D.

Record any reference codes shown and provide them to Apple or your support provider.

A clean diagnostic result does not rule out every intermittent display or dock problem, but it is a useful hardware check.

When the Mac May Need Repair

Arrange professional inspection when:

The built-in screen remains black after restart
The Mac wakes only when pressure is applied to the lid
The screen flickers at certain angles
You see lines, patches or distorted colours
The Mac shuts down unexpectedly
The battery is swollen
The case is separating
Liquid damage is suspected
Apple Diagnostics reports a fault
The Mac repeatedly needs forced shutdowns
The issue occurs even in Safe Mode with no accessories

A screen that changes as the lid moves may indicate a display cable or panel problem rather than a sleep issue.

A Sensible Troubleshooting Order

When a Mac will not wake from sleep, use this order:

Press a key, click the trackpad and open the lid.
Increase screen brightness.
Connect the charger directly.
Wait several minutes if the battery may be flat.
Disconnect accessories and external displays.
Restart the Mac.
Reconnect the display directly without a dock.
Check the monitor input, cable and adapter.
Use Detect Displays.
Reduce resolution and refresh rate.
Install macOS, dock and monitor updates.
Review login items and background applications.
Test in Safe Mode.
Reset the SMC only on an Intel Mac.
Run Apple Diagnostics.
Arrange repair if the built-in display or power system remains unreliable.

The most important distinction is whether the Mac has failed to wake or whether it has woken but cannot display an image.

Need Help with a Mac That Will Not Wake?

Intermittent sleep problems can be caused by macOS, external monitors, USB-C docks, background software, batteries or display hardware. Repeatedly forcing the Mac off may appear to solve the problem but risks lost work and does not address the underlying cause.

Hamilton Group can diagnose Mac sleep and display issues, test docks and peripherals, update the relevant software and determine whether the fault is software-related or requires hardware repair.

Call 0330 043 0069 or visit hgmssp.com to speak with one of our IT experts.