Central Theft Deterrent (CTD) Relearn
NOTE:
After installing NEW control modules, perform CTD relearn procedure. If CTD relearn procedure is not performed, ignition switch transponder information will not be learned by other control modules on class 2 data bus circuit. When attempting to start vehicle, engine may not crank or start.
Perform CTD relearn procedure if BCM, PASS-Key(R) III (PK3) module, Powertrain Control Module (PCM) and/or ignition lock cylinder have been replaced. For Content Theft Deterrent (CTD) relearn procedures and customization settings of anti-theft system (if equipped). See ANTI-THEFT SYSTEMS - MONTANA, SILHOUETTE & VENTURE article.