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 these procedures after replacing:
| • | Passlock™ Sensor | 
| • | BCM | 
| • | PCM | 
None
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.