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Home >> Cadillac >> 2017 >> CTS Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 178 (Immobilizer System) >> Diagnostic Information and Procedures >> DTC B3935: Transponder Authentication Error >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page is about a different car, the 2016 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Replace the suspected inoperative or malfunctioning transmitter.
  2. Verify DTC B3935 is not set as current.
    • If the DTC is set as current 

      Replace the K9 Body Control Module.

    • If the DTC is set as history 
  3. All OK.