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Home >> Buick >> 2000 >> LeSabre Custom, 4T65E/MN3 >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Anti-Theft System) >> Diagnostic Tests >> DTC B3031: Key Decoder In Assembly Learn Mode >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2000 Pontiac Bonneville. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform auto learn procedure. See PASS-KEY(R) III 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 B3031 does not exist, system is okay.
  2. Replace VTD module. 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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