The issue you have encountered is an operational anomaly which may occur with both the Macintosh PowerBook 500 and 5300 series computers. Also, it should be noted that this same scenario can happen when one of these PowerBook computer models is connected to ANY desktop Macintosh computer, not just the Macintosh Performa 6200 series computers.
If you follow the directions in the PowerBook user's guide, which instructs the you to power down the desktop Macintosh computer before powering down the PowerBook, the PowerBook computer may lock up. This forces you to use the power/reset switch on the back of the PowerBook computer to shut it down. This shutdown method is not advised because it may corrupt the power manager of the PowerBook computer.*
Workaround
1. Highlight the PowerBook computer's hard drive in the Finder on the desktop of the desktop Macintosh computer by clicking on its icon.
2. Select "Put Away" (Command Y) from the File menu to unmount the PowerBook computer's hard drive. (It should disappear from the desktop.)
3. Press and hold the power key (upper right corner of the keyboard) on the PowerBook computer's keyboard for approximately three seconds, then release it. This will shut down the PowerBook safely.
For more information on resetting the Power Manager on Macintosh PowerBook computers, please see the following Tech Info Library article:
Article 14449: "
PowerBook: Resetting Power Manager"
This article was published in the Information Alley on 3 September 1996.