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Home >> Cadillac >> 2000 >> DeVille Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Anti-Theft System >> Diagnostic Tests >> DTC B3031: Key Decoder Device In Assembly Learn Mode >> Diagnostic Procedure
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Diagnostic Procedure

  1. Perform auto learn procedure. See VEHICLE THEFT DETERRENT SYSTEM AUTO LEARN PROCEDURE  under PROGRAMMING. Turn ignition off. Using scan tool, clear DTCs. Turn ignition off. Turn ignition on. If DTC B3031 exists, go to next step. If DTC does not exist, system is okay.
  2. Replace VTD module. See REMOVAL & INSTALLATION in STEERING COLUMN SWITCHES - DEVILLE article. After repairs, go to next step.
  3. Turn ignition off. Reconnect all connectors. Turn ignition on. Using scan tool, clear DTCs and recheck system operation.
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