How to Fix a Non-Booting Mac

Apple computers also experience booting problems.

A Mac computer can experience start-up or booting problems for a number of reasons. Although a non-booting Mac is a cause for concern, minor glitches such as loose connections, power issues and problems with peripherals may be causing your start-up problems. However, you may also need to reset your Mac's System Management Unit (SMU) if conventional troubleshooting steps fail to resolve the problem. Your Mac's power functions are controlled by the SMU.

Instructions

Physical Connections

1. Check the Mac's power cord and outlet for functionality; and see that the plug is properly inserted and the outlet has power. Also check your fuse box to make sure the fuse that is managing electricity to the wall outlet is not tripped.

2. Remove all peripherals connected to the Mac, such as an external mouse. If a peripheral is causing your Mac to have problems starting up, disconnecting it will solve the problem. Press the "Power" button on the Mac to see if it boots up after removing the peripherals.

3. Disconnect the power cable from the Mac, and then re-connect it. If the power cable is not properly inserted into the Mac, it will not boot up.

4. Check the Mac's power cable for cuts or fraying. If the cable is damaged, it will not supply power to your Mac. Replace the cable if you see any signs of disrepair.

SMU Reset

1. Remove any cables that are connected to the Mac, and then wait for 10 seconds.

2. Re-connect the power cable, and then press and hold the "Power" button at the same time.

3. Release the "Power" button, and then press it again to boot the Mac.

References

• Apple: Troubleshooting: My Computer Won't Turn On
• Apple: How to Reset the SMU