I have seen the BCM out which cause this problem. Here are the security system wiring diagrams so you can see how the system works and the location of the BCM which will need to be programmed to work.
Body Control Module (BCM) Programming/RPO Configuration
Important: If the module is replaced, programming the module with the proper RPO configurations must be done prior to performing the Passlock Learn procedure.
The BCM must be programmed with the proper RPO configurations. The BCM stores the information regarding the vehicle options. If the BCM is not properly configured with the correct RPO codes the BCM will not control the features properly. Ensure that the following conditions exist in order to prepare for BCM programming:
The battery is fully charged.
The ignition switch is in the RUN position.
The DLC is accessible.
All disconnected modules and devices are reconnected before programming.
Follow the SPS instructions on the Techline Terminal and scan tool to program the BCM.
If the BCM fails to accept the program, perform the following steps:
Inspect all BCM connections.
Verify that the SPS Techline Terminal and scan tool have the latest software version.
Passlock Learn Procedures
Refer to PROGRAMMING THEFT DETERRENT SYSTEM COMPONENTS for the appropriate learn procedure.
Important: After programming, perform the following to avoid future misdiagnosis.
Turn the ignition OFF for 10 seconds.
Connect the scan tool to the data link connector.
Turn the ignition ON with the engine OFF.
Use the scan tool in order to retrieve history DTCs from all modules.
Clear all history DTCs.
I would try unplugging the BCM and then plugging it in again which can solve a bad connection issue.
Check out the diagrams (Below). Please let us know what you find. We are interested to see what it is.
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Thursday, May 13th, 2021 AT 6:59 PM