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Home >> Cadillac >> 2017 >> CTS Base, AWD >> Repair and Diagnosis >> Body & Frame >> Ignition Switch/Steering Lock >> Immobilizer System >> Diagnostic Information and Procedures >> DTC P0633: Immobilizer Key Not Programmed >> Circuit/System Verification
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Circuit/System Verification

NOTE:

DTC P0633 will clear upon a successful engine start. Any malfunction that will cause a no-start condition will prevent DTC P0633 from clearing. Prior to diagnosing DTC P0633, ensure that all power moding and engine control systems are operating properly and all conditions that may cause a no-start have been corrected. Do not replace the K20 Engine Control Module. Replacing the K20 Engine Control Module will not correct the no-start condition.

  1. Verify there are no immobilizer DTCs set in the K9 Body Control Module.
    • If no immobilizer DTCs are set in the K9 Body Control Module 
  2. Perform the K20 Engine Control Module immobilizer learn using the engine control module IMMO Learn in SPS. Refer to Immobilizer System Component Programming .
  3. Verify the engine starts after the K20 Engine Control Module completes the learn procedure.
    • If the engine does not start 

      An undiagnosed no-start condition exists. Refer to the appropriate subsection and diagnostic to correct the no-start condition.

    • If the engine starts 
  4. All OK.
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