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DTC P1649

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P1649: Immobiliser Security Code Not Programmed

Circuit/System Description

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.

Conditions for Running the DTC

The ECM is in learn mode.

Conditions for Setting the DTC

The ECM has not learned a security code.

Action Taken When the DTC Sets

The security indicator in the instrument cluster will illuminate.

Conditions for Clearing the DTC
    • A current DTC P1649 will be cleared upon a successful engine start after exit of learn mode.
    • A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Reference Information

Schematic Reference

Immobiliser Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobiliser Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References

Circuit/System Verification

Note: Because of normal system communications between the BCM and ECM, any immobiliser DTCs set in the BCM must be diagnosed prior to the diagnosis immobiliser DTCs set in the ECM.

  1. Perform the ECM immobiliser learn using the Engine Control Module IMMO Learn in SPS. Refer to Immobiliser System Component Programming .
  2. Verify the ECM successfully completes the learn procedure and the vehicle starts.
    3. [ARW-LISTFAIL]

  3. If the ECM does not successfully learn or the engine does not start

    Replace the K20 ECM.

    4. [/ARW-LISTFAIL][ARW-LISTPASS]

  4. If the vehicle starts

    5. [/ARW-LISTPASS]
  5. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

   


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