GM Service Manual Online
For 1990-2009 cars only

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 012: Engine Not Running - No Reference Pulse

Circuit/System Description

This is a normal code that the electronic control module (ECM) stores.

Conditions for Setting the DTC

The ignition is ON, and the engine is OFF.

Diagnostic Aids

    • This code indicates a normal condition with no malfunctions.
    • This code indicates that the ECM has the ability to store codes.
    • If other DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for the applicable DTC.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for engine control module replacement, setup, and programming.