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Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis (Single Page) >> Body & Frame >> Ignition Switch/Steering Lock >> Immobilizer System >> Diagnostic Information and Procedures >> DTC B389A: Environment Identification >> Circuit/System Verification
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Circuit/System Verification

  1. Verify DTC B389A did not set immediately following the replacement and programming of the K9 Body Control Module.
    • If the DTC set immediately after the replacement and programming of the K9 Body Control Module 

      The immobilizer learn procedure was not properly completed. Perform the BCM immobilizer learn using the body control module IMMO Function with Existing Transponder or Remote Key in SPS. Refer to Immobilizer System Component Programming .

    • If the DTC did not set immediately after the replacement and programming of the K9 Body Control Module 
  2. Verify DTC B3902 is not set in any of the control modules listed below:
    • K20 Engine Control Module
    • K36 Inflatable Restraint Sensing and Diagnostic Module
    • K17 Electronic Brake Control Module
    • K33 HVAC Control Module
    • P16 Instrument Cluster
    • K60 Steering Column Lock Module (if equipped)
    • If DTC B3902 is set in any of the modules 

      Refer to DTC B3902 .

    • If DTC B3902 is not set in any of the modules 
  3. Perform the K9 Body Control Module immobilizer learn using body control module IMMO Function with Existing Transponder or Remote Key in SPS. Refer to Immobilizer System Component Programming .
  4. Verify DTC B389A does not set after programming.
    • If the DTC sets after programming 

      Replace the K9 Body Control Module.

    • If the DTC does not set after programming 
  5. All OK.
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