This thread thoroughly answers this question. Would cut & paste text, but it won't let me.
http://www.automotiveforums.com/t151485.html
Take the remote apart and it says to push the buttons once each or twice each try this
the remote has been lost and a new remote has been purchased. i had to remove the fuse to get the alarm to stop. how can i reset the alarm? So i can program the new remote.
how do I program a garage door opener for a 2002 chevy venture
how do you program your keyless remote for 2003 Chevy blazer
How do you program the remote key fob on a 2005 Chevy Malibu maxx
How do i you program keyless remote for a 2004 malibu?
I have a use remote that I need to program
The door lock remote control receiver for a 1997 Chevy Astro van is located inside the cabin. it is found on the right kick plate.
You need a gm scanner to program a factory gm remote fobs.
How program my keyless entry remotes for 2003 chevy malibu
You will need to contact a dealership to program the remote key FOB on a 2001 Chevy Malibu. Stock remotes can only be programmed at Chevy dealerships.
This vehicle requires a scan tool to program the remote, a dealer or locksmith will have to do it.