Is this the relearn procedure you've been trying?
Time required, approximately 30 minutes.
1. Ensure that the battery is fully charged. 2. Use the scan tool to clear the DTCs. 3. Turn the ignition switch from the OFF position to the CRANK position allowing the vehicle to try and start. The vehicle will start and then stall. 4. Leave the ignition switch in the ON position while observing the security indicator. 5. When the security indicator turns off, which can take up to 10 minutes, turn the ignition switch off. Wait 10 seconds. 6. Repeat Steps 3-5 2 more times (3 times total).
The BCM and the PCM/VCM will learn the new code on the next start attempt.