Apple Powerbank G4 Resetting the Power Manager Unit (PMU)

8 - PowerBook G4 (17-inch) Troubleshooting General Information
Apple Service Diagnostic Hardware info tab
Apple Service Diagnostic Test log tab
Resetting the Power Manager Unit (PMU)
The PMU reset button has been removed from the logic board. Use the following key
combination procedure or the PMU Reset pad (see PMU NMI and PMU Reset pads on
logic board, below).
1. If the computer is on, turn it off.
2. Reset the power manager by simultaneously pressing and then releasing Shift-
Control-Option-power button. Do not press the fn (Function) key while using this
combination of keystrokes.
3. Wait 5 seconds.
4. Press the power button to restart the computer.