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Home >> Buick >> 2016 >> Encore Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 33 (Immobilizer System) >> Diagnostic Information and Procedures >> DTC P1649: Immobilizer Security Code Not Programmed >> Circuit/System Description
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Circuit/System Description

WARNING: This page is about a different car, the 2015 Chevrolet Trax and 2015 Buick Encore. However, it is still accessible from the selected car via links, so may be relevant.

When learning the security code, as well as the challenge and response sequence, the engine control module (ECM) is placed in learn mode. Once the security code and challenge/response are learned, learn mode will be exited when the engine is successfully started.