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It appears that your CMOS (backup) battery may be dead. That would account for the 163 and 173 errors. You may or may not also get a 161 error. Download a copy of the Hardware Maintenance Manual for the 600/600E from here:
http://www-307.ibm.com/pc/support/site. ... WIK-3SYPX2
It contains information about the errors and instructions on how to change the battery. It is located in the memory bay, tucked up between the front edge of the laptop and plugs into the motherboard.
be able to access the BIOS by holding down the F1 key while the laptop is powered on, and continue holding it down until you get the "Easy Setup" (BIOS) menu.