Service Information

Volt

DTC P0633

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 P0633: Immobiliser Key Not Programmed

When learning the immobiliser data, as well as the challenge and response sequence, the engine control module (ECM) is placed in learn mode. DTC P0633 will set automatically as an indicator that the system is in learn mode and not as a fault indicator. Once the immobiliser data and challenge/response are learned, learn mode will be exited when the engine is successfully started. If the ECM does not exit learn mode, DTC P0633 will remain current and indicate a fault.

Conditions for Running the DTC

The ECM is in learn mode.

Conditions for Setting the DTC

DTC P0633 will set any time the ECM enters learn mode.

Action Taken When the DTC Sets

The security indicator in the instrument cluster will illuminate.

Conditions for Clearing the DTC

•	A current DTC P0633 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

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Note: DTC P0633 will clear upon a successful engine start. Any malfunction that will cause a no-start condition will prevent DTC P0633 from clearing. Prior to diagnosing DTC P0633, ensure that all power mode and engine control systems are operating properly and all conditions that may cause a no-start have been corrected.

Verify there are no immobiliser DTCs set in the BCM.

⇒	*If any immobiliser DTCs are set in the BCM*

Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

⇓	*If no immobiliser DTCs are set in the BCM*

Perform the ECM immobiliser learn using the Engine Control Module IMMO Learn in SPS. Refer to Immobiliser System Component Programming .
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*

All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for ECM replacement, programming, and setup