Important: Due to component variability, the vehicle theft deterrent (VTD) system must have the learn procedure performed regardless, if the vehicle starts on the first ignition cycle after a VTD repair.
All codes in the theft deterrent module must be cleared for a relearn.Important: 
   •  The body control module (BCM) must be programmed with the proper  RPO
   configurations before performing learn procedures.  Refer to 
Body Control Module (BCM) Programming/RPO Configuration 
 in Body   Control   System.    •  If replacing the BCM with a GM Service Parts Operations (SPO)  replacement
   part, the module will learn passlock™ sensor data  code    immediately.
     The existing PCM however, must learn the new fuel continue     password
   when  the  BCM is replaced.    •  If replacing a PCM with a GM Service Parts Operations (SPO) replacement
    part, after programming,  these modules will learn the incoming fuel continue
        password immediately  upon receipt of a password message. Once a password
       message  is received,  and a password is learned, a learn procedure
 must      be  performed  to change  this password again. A PCM which has
been  previously       installed  in another  vehicle will have learned the
other  vehicle's  fuel     continue  password  and  will require a learn procedure
 after programming      to learn the  current  vehicle's  password. 
Use this procedure after replacing any of the following:
| • | Passlock™ Sensor | 
| • | BCM | 
| • | PCM | 
Important: The vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.