Not sure what year you have. Here is the +'98 procedure.
NOTE: If the steps are not performed as outlined, the programming procedure will end.
NOTE: Ignition keys must have correct mechanical key cut for the vehicle and must be a PATS encoded key.
Insert first programmed ignition key into ignition lock cylinder and turn ignition switch from OFF to RUN (maintain ignition switch in RUN for 1 second.
Turn ignition switch to OFF and remove first key from ignition lock cylinder.
Within 5 seconds of turning the ignition switch to OFF, insert the second programmed ignition key into the ignition lock cylinder and turn the ignition switch from OFF to RUN (maintain ignition switch in RUN for 1 second).
Turn ignition switch to OFF and remove second key from ignition lock cylinder.
Within 10 seconds of turning the ignition lock cylinder to OFF, insert the unprogrammed ignition key (new key) into the ignition lock cylinder and turn the ignition switch from OFF to RUN (maintain ignition switch in RUN for 1 second).
If it is desired to program additional key(s), repeat the Key Programming Procedure from the beginning.
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Here is the '96-'97 procedure.
NOTE: Encoded keys must have correct mechanical key cut for vehicle.
Cycle ignition switch from RUN to OFF with a programmed key.
Within 15 seconds after this cycle, insert a new encoded key into ignition switch and turn to RUN or START.
If programming is successful, the THEFT Indicator will illuminate for two seconds and the control module will enable the vehicle to start.
Repeat until all chosen keys have been programmed, up to 16 keys total.
If programming is not successful, the THEFT Indicator will:
Flash for one minute if no key code is received. The key is either damaged or is a non-encoded key. (Try a new key and start procedure over again.)
Flash for 15 minutes if key code is received yet vehicle is disabled. The key was not programmed successfully. Start procedure over again.
If programming is not successful, possibly the new key was not inserted within 15 seconds, all 16 key codes have been stored, or the key is a non-encoded key. If the key was not encoded or inserted within 15 seconds, repeat procedure.