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Home >> Cadillac >> 2018 >> CT6 Plug-In >> Repair and Diagnosis >> Body & Frame >> Ignition Switch/Steering Lock >> Immobilizer System >> Diagnostic Information and Procedures >> DTC B305C >> Circuit/System Verification
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Circuit/System Verification

  1. Ignition ON.
  2. Verify all available keys/transmitters are correct for the vehicle. This can be accomplished by comparing the part number that is laser etched on the key to the part number listed in the parts catalog.
    • If a key is not correct 

      Replace the appropriate key.

    • Go to next step: If all keys are correct 
  3. Verify the scan tool Key Part Number parameter displays a Key Part Number when turning the ignition ON with each key.
    • If a Key Part Number is not read 

      Replace the appropriate key.

    • Go to next step: If a Key Part Number is read for each key 
  4. All OK.