Caution: Resetting parameter RAM (PRAM) erases the contents of the RAM disk, if there is one. Resetting PRAM also restores the default settings in most control panels. After you reset PRAM, be sure to check any custom settings for the desktop pattern, memory, network, AppleTalk, trackpad, power conservation, and so forth.
Reset/zap PRAM from the shutdown state. Note that resetting PRAM when the computer is shut down also resets the power manager.
Follow these steps to reset PRAM: 1 Unplug the AC adapter.
2 Power on the computer by pressing the Power key.
3 Immediately hold down the Option-Command-P-R keys.
4 Keep holding down these four keys until you have heard the startup chime at least one additional time after the initial startup chime.
(If the PowerBook emits multiple chimes when you are holding down the Option-Command-P-R keys, skip to Step 7.)
Note: Unlike other PowerBook models, these PowerBook computers often emit only a single startup chime. Then the screen goes dark/blank and the green sleep light stays on (it does not blink on and off as it does when the computer is in sleep mode).
5 Press the Reset button once and, after a brief pause, the PowerBook should start up.
Note: If the PowerBook powers off and the sleep display light stays a solid green with no blinking, press the Reset button again.
6 If the PowerBook does not power on from the Reset button, turn the PowerBook on by pressing the Power key.
7 After the computer has started up, select Shut Down from the Special menu.
8 Plug in the AC adapter. If the computer remains shut down, you will know that you have successfully reset the PRAM and power manager and your computer should now function normally. If, however, the computer powers on when you plug in the AC adapter, you need to reset the power manager.
Resetting the Power Manager
Follow these steps to reset the power manager:
1 Remove the battery.
2 Disconnect the AC adapter from the PowerBook and unplug it from the wall outlet.
3 Press and hold the Reset button for one minute.
4 Plug the AC adapter into the wall outlet.
5 Connect the AC adapter to the PowerBook. It should now behave normally when you choose Shut Down from the Special menu.
The Control Strip on the PowerBook 1 90/5300 Series desktop indicates the battery charge and the rate at which the battery is being used. To determine the actual battery charge, use a voltmeter:
1 Set the voltmeter appropriately so it is able to measure 14 volts on the DC scale.
2 Hold the positive probe of the voltmeter to the positive battery terminal and the negative probe to the negative terminal.
3 A fully charged battery measures 14 volts; a PC fully discharged battery measures 7.8 volts.
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