This process resets both the Power Manager and revives PowerBook 5300 and 190 computers which do not initially turn on.
1. Unplug AC adapter and remove battery.
2. Press and hold the Reset button on the back of the machine for about 45 seconds. (See chart below for location of the reset button.)
3. Plug the AC Adapter into the AC (wall) outlet.
4. Attach only the AC adapter to the PowerBook (don't put in the battery).
5. Press the Reset button one more time and the PowerBook should startup after a brief pause.
| PowerBook | Reset Button Location (on rear of computer) |
| 190 Series | Below the video out port |
| 5300 Series | Below the video out port |
Note: The Power Manager code can be fully purged by having an authorized service technician disconnect the internal backup battery and let the unit sit for 1 minute with all power removed (including the main battery and the AC Adapter). This forces the PowerBook to reload the code from the system software.
Authorized Apple Service technicians may remove the internal back up battery to reset the Power Manager. If you are not an authorized Apple Service technician, please note that removing the internal backup battery is not a simple procedure and is not recommended. If anything is damaged in your attempt to remove the battery, it will not be covered under warranty.