Apple iMac G5, 20-inch - Manual (Page 257)

iMac G5, 20-inch Troubleshooting - 33 Symptom Charts
10. Does the computer start up normally after pressing the internal power button?
Yes: Press and hold the power button until the computer powers off.
• Unplug the power cord from the iMac, and reinstall the back cover.
• Return the computer to the upright position.
• Plug the computer back in, and press the power button to turn on the computer.
• Make sure the computer is starting up properly. If the computer will ONLY start up
from the internal power but will not power on from the power button on the back
cover, the power button on the back cover may be faulty. Go to step 13
No: Press the SMU reset button to reset system power management. The SMU is the
small metal button (shown below) located below the internal power button.
11. After pressing the SMU button, press the internal power button again. Does the
computer start up normally now?
Yes: Press and hold the power button until the machine powers off.
• Unplug the power cord from the iMac, and replace the back cover.
• Return the computer to the upright position.
• Plug the in the computer, and press the power button to turn on the computer.
• Make sure the computer is starting up properly. If the computer will ONLY start up
from the internal power but will not power on from the power button on the back
cover, this may indicate that the power button on the back cover is faulty. Got to
step 13.
No: Go to the next step.
12. Unplug the power from the iMac G5 and remove the internal hard drive and set it
aside. Plug in the iMac G5, and using the Internal power button as before, power on
the iMac G5. Does the iMac G5 start up now?