My Thinkpad 600 has the standard error codes for time & date (161 &163)! After changing out the CMOS battery (which many times corrects this problem) and pressing F1, I still get the same error codes and a "locked out padlock" symbol! Seams to be an endless loop!

Kent Adams, December 2007

Try downloading a hardware maintenance manual from www.lenovo.com and following the diagnostic sequence.

It may have a BIOS password set.

t, December 2007