P1649

DTC P1649

Diagnostic Instructions

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

DTC Descriptor
DTC P1649
- Immobilizer 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

Immobilizer Schematics Immobilizer Schematics
Connector End View Reference

Component Connector End Views Sunshade - Left (D6I)
Description and Operation

Immobilizer Description and Operation Immobilizer
Electrical Information Reference

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

Scan Tool Reference

Control Module References Control Module References

Circuit/System Verification

1. Verify there are no immobilizer DTCs set in the BCM.

• If any immobilizer DTCs are set in the BCM
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

• If no immobilizer DTCs are set in the BCM

2. Perform the ECM immobilizer learn using the Engine Control Module IMMO Learn in SPS. Refer to Immobilizer System Component Programming (without BTM) Immobilizer System Component Programming (without BTM)Immobilizer System Component Programming (with BTM) Immobilizer System Component Programming (with BTM).
3. Verify the engine starts after the ECM completes the learn procedure.

• If the engine does not start
Replace the K20 engine control module.

• If the engine starts

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Control Module References Control Module References for ECM replacement, programming, and setup