If an M4 Mac mini will not start, check the power button first: it is on the underside near the back left corner, so it is easy to miss. Then check the power cable at both ends, connect a display by HDMI or Thunderbolt to tell a dead Mac from a blank screen, and hold the power button for about ten seconds to reach startup options. A Mac mini with no light, no fan sound and no response after that needs Apple service.
Differential
Likely causes of “Apple Mac mini M4 will not turn on or start”, and how to tell them apart
- 1
The power button was not pressed
What separates it Nothing happens because the button is under the case, not on top
How to confirm Tilt the Mac mini and press the button near the back left corner
- 2
No power at the cable or outlet
What separates it No light and no fan sound at all
How to confirm Reseat the power cable at the Mac mini and the wall, and try another outlet
- 3
A blank display, not a dead Mac
What separates it A light or fan shows life but the screen says No Signal
How to confirm Try another HDMI cable or a Thunderbolt display connection and another input
- 4
A software or wake problem
What separates it It goes to sleep and will not wake, or a monitor shows No Signal after sleep
How to confirm Hold the power button for ten seconds, restart, then install the latest macOS update
- 5
Firmware that needs reviving
What separates it It shows a flashing exclamation mark or never starts after an update
How to confirm Use Apple Configurator from another Mac to revive or restore the firmware
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether any light or sound shows when you press the button
- Which display cable and port you are using
- Whether the Mac mini went to sleep and failed to wake
- The macOS version
Try in this order
0 of 6 completedFind and press the power button
ReversibleOn the M4 Mac mini the button is on the underside near the back left corner; lift or tilt the small case to press it.
Check the power cable
ReversibleReseat the cable at the Mac mini and the wall and try another outlet; look for any light.
Check the display connection
ReversibleConnect the monitor with a different HDMI cable or to a Thunderbolt port, and select the right input on the monitor.
Hold the power button for ten seconds
ReversibleOn Apple silicon, holding the button shows Loading startup options; choose your startup disk and Continue.
Install macOS updates
ReversibleOnce it starts, install the latest macOS update; owners reported wake-from-sleep failures that later updates addressed.
Revive or restore with another Mac
ReversibleIf it will not start, connect it to another Mac with a USB-C cable and use Apple Configurator to revive or restore the firmware.
Model-specific
What is true of this model and not of its siblings
- Other desktops on this page
- The iMac has its power button on the back edge and the Mac Studio has it on the back panel; the cable and display checks are the same.
- Repair cost
- An out-of-warranty logic board or power supply repair at Apple or an independent shop usually costs more than a cable, a display cable or a firmware restore, which are free to try.
- Other models this page answers
- These steps also fit the iMac 24-inch (M4), Mac Studio (M2 Max/M2 Ultra).
Stop boundary
When this stops being a self-service repair
- !If nothing responds after the cable and button checks, contact Apple Support
- !If it smells or crackles, unplug and stop
- !If revive and restore fail, book service
Evidence ledger
Sources behind this answer
Power cable, external display, 10-second power button hold, accessories and SMC on Intel Macs.
Blank screen at startup, Recovery, firmware and service.
What each startup screen means.
Four Thunderbolt 4 ports, up to two external displays, camera, speakers, Ethernet and weight.
M4 and M4 Pro ports, HDMI, Ethernet, display support, speaker, Wi-Fi 6E and weight.
M2 Max and M2 Ultra ports, SDXC slot, HDMI, 10Gb Ethernet, display support, speaker and weight.
AppleCare+ service fees for Mac models: $49 to $99 for damaged screens or external enclosures and $149 to $299 for other accidental damage.
Owners reporting wake-from-sleep failures.
Where the power button moved to.
Exact questions
Common questions
Where is the power button on an M4 Mac mini?+
On the underside near the back left corner, in the recess by the vents. You lift or tilt the Mac mini to reach it.
Why does my Mac mini show No Signal after sleep?+
MacRumors owners reported this after macOS Tahoe updates, with keyboard presses doing nothing. Holding the power button and restarting clears it; updating macOS is the fix.
Can I start a Mac mini with the keyboard?+
An Apple silicon Mac mini starts from the power button, and a connected keyboard can wake it from sleep but not turn it on from off.
Do iMac and Mac Studio use the same steps?+
The power checks are the same, but the button is on the back of the iMac and of the Mac Studio.