fisherdm, sorry but your BCM is bad. It's not the PK system although it could be on its way out too. I had a '01 S10 in the shop for the same thing. The security light would be lit even when the key was removed. If you unplugged the BCM it'd go out and you could get the car to start when you plugged it back in. Then, a few times later it'd lock up once again. After doing some scans it was found out the BCM was bad. After $423 in buying a new BCM, it was fine. That's been about 3 months ago.