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Home >> GMC >> 2006 >> Sierra 1500 HD, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 257 (Theft Deterrent System) >> Diagnostic Information and Procedures >> DTC P1631: PCM Did Not Receive A Valid Password >> Test Description

Test Description

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The numbers below refer to the step numbers on the diagnostic table.

  1. 2. This DTC may set as a result of other Passlock System problems. Diagnose any BCM DTCs prior to continuing with this diagnostic.
  2. 3. A DTC B3031 may set in the body control module (BCM) during the Password Learn Procedure.
    Fig 1: Identifying DTC P1631 Diagnostic Table
    G02422731Courtesy of GENERAL MOTORS CORP.