Section 14 (Anti-Theft System): Programming: Notes
WARNING: This page is about a different car, the 2002 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
If a Powertrain Control Module (PCM) is replaced on a vehicle equipped with the Sentry Key Immobilizer System (SKIS), the unique Secret Key data must be transferred from the Sentry Key Immobilizer Module (SKIM) to the new PCM using the PCM replacement procedure. This procedure also requires the use of a DRBIII(R) scan tool and the unique four-digit PIN code to enter the Secured Access Mode in the SKIM. See BODY CONTROL MODULES - LIBERTY
article.