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Home >> Buick >> 2012 >> Regal Base >> Repair and Diagnosis >> Body & Frame >> Ignition Switch/Steering Lock >> Immobilizer System >> Diagnostic Information and Procedures >> DTC P1649 >> Circuit/System Verification
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Circuit/System Verification

  1. Verify there are no immobilizer DTCs set in the BCM.
    • If no immobilizer DTCs are set in the BCM 
  2. Perform the ECM immobilizer learn using the Engine Control Module IMMO Learn in SPS. Refer to Immobilizer System Component Programming (without BTM) , Immobilizer System Component Programming (with BTM) .
  3. Verify the engine starts after the ECM completes the learn procedure.
    • If the engine does not start 

      Replace the K20 engine control module.

    • If the engine starts 
  4. All OK